

<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.tree.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetailsBalanceSheet" xlink:href="tree-20180331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesDetailsBalanceSheet" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/AccruedExpensesAndOtherCurrentLiabilitiesNote" xlink:href="tree-20180331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:href="tree-20180331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/BusinessAcquisitionDetails" xlink:href="tree-20180331.xsd#BusinessAcquisitionDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/BusinessAcquisitionNote" xlink:href="tree-20180331.xsd#BusinessAcquisitionNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/BusinessAcquisitionTables" xlink:href="tree-20180331.xsd#BusinessAcquisitionTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/CashAndRestrictedCashDetailsBalanceSheet" xlink:href="tree-20180331.xsd#CashAndRestrictedCashDetailsBalanceSheet" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/CashAndRestrictedCashNote" xlink:href="tree-20180331.xsd#CashAndRestrictedCashNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/CashAndRestrictedCashTables" xlink:href="tree-20180331.xsd#CashAndRestrictedCashTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ConsolidatedBalanceSheets" xlink:href="tree-20180331.xsd#ConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:href="tree-20180331.xsd#ConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ConsolidatedStatementOfShareholdersEquity" xlink:href="tree-20180331.xsd#ConsolidatedStatementOfShareholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ConsolidatedStatementsOfCashFlows" xlink:href="tree-20180331.xsd#ConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ConsolidatedStatementsOfOperationsAndComprehensiveIncome" xlink:href="tree-20180331.xsd#ConsolidatedStatementsOfOperationsAndComprehensiveIncome" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ContingenciesDetails" xlink:href="tree-20180331.xsd#ContingenciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ContingenciesNote" xlink:href="tree-20180331.xsd#ContingenciesNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DebtDetailsConvertibleNoteHedgeAndWarrantTransactions" xlink:href="tree-20180331.xsd#DebtDetailsConvertibleNoteHedgeAndWarrantTransactions" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DebtDetailsConvertibleSeniorNotes" xlink:href="tree-20180331.xsd#DebtDetailsConvertibleSeniorNotes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DebtDetailsRevolvingCreditFacility" xlink:href="tree-20180331.xsd#DebtDetailsRevolvingCreditFacility" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DebtNote" xlink:href="tree-20180331.xsd#DebtNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DebtTable" xlink:href="tree-20180331.xsd#DebtTable" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DiscontinuedOperationsDetailsDisposalGroups" xlink:href="tree-20180331.xsd#DiscontinuedOperationsDetailsDisposalGroups" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DiscontinuedOperationsDetailsLoanLossObligations" xlink:href="tree-20180331.xsd#DiscontinuedOperationsDetailsLoanLossObligations" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DiscontinuedOperationsNote" xlink:href="tree-20180331.xsd#DiscontinuedOperationsNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DiscontinuedOperationsTables" xlink:href="tree-20180331.xsd#DiscontinuedOperationsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/DocumentAndEntityInformation" xlink:href="tree-20180331.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/FairValueMeasurementsDetails" xlink:href="tree-20180331.xsd#FairValueMeasurementsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/FairValueMeasurementsNote" xlink:href="tree-20180331.xsd#FairValueMeasurementsNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/FairValueMeasurementsTables" xlink:href="tree-20180331.xsd#FairValueMeasurementsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/GoodwillAndIntangibleAssetsDetails5YrDefiniteLivedIntangiblesAmortization" xlink:href="tree-20180331.xsd#GoodwillAndIntangibleAssetsDetails5YrDefiniteLivedIntangiblesAmortization" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/GoodwillAndIntangibleAssetsDetailsBalanceSheet" xlink:href="tree-20180331.xsd#GoodwillAndIntangibleAssetsDetailsBalanceSheet" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/GoodwillAndIntangibleAssetsDetailsDefiniteLivedIntangibles" xlink:href="tree-20180331.xsd#GoodwillAndIntangibleAssetsDetailsDefiniteLivedIntangibles" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/GoodwillAndIntangibleAssetsGoodwillAndIntangibleAssetsDetailsNarrativeDetails" xlink:href="tree-20180331.xsd#GoodwillAndIntangibleAssetsGoodwillAndIntangibleAssetsDetailsNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/GoodwillAndIntangibleAssetsNote" xlink:href="tree-20180331.xsd#GoodwillAndIntangibleAssetsNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/GoodwillAndIntangibleAssetsTables" xlink:href="tree-20180331.xsd#GoodwillAndIntangibleAssetsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/IncomeTaxesDetails" xlink:href="tree-20180331.xsd#IncomeTaxesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/IncomeTaxesNote" xlink:href="tree-20180331.xsd#IncomeTaxesNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/IncomeTaxesTables" xlink:href="tree-20180331.xsd#IncomeTaxesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/OrganizationNote" xlink:href="tree-20180331.xsd#OrganizationNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/RevenueDetails" xlink:href="tree-20180331.xsd#RevenueDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/RevenueNote" xlink:href="tree-20180331.xsd#RevenueNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/RevenueScheduleOfRevenueTables" xlink:href="tree-20180331.xsd#RevenueScheduleOfRevenueTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SegmentInformationDetails" xlink:href="tree-20180331.xsd#SegmentInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SegmentInformationNote" xlink:href="tree-20180331.xsd#SegmentInformationNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SegmentInformationTables" xlink:href="tree-20180331.xsd#SegmentInformationTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ShareholdersEquityDetails" xlink:href="tree-20180331.xsd#ShareholdersEquityDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ShareholdersEquityNote" xlink:href="tree-20180331.xsd#ShareholdersEquityNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/ShareholdersEquityTables" xlink:href="tree-20180331.xsd#ShareholdersEquityTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SignificantAccountingPoliciesDetails" xlink:href="tree-20180331.xsd#SignificantAccountingPoliciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SignificantAccountingPoliciesNote" xlink:href="tree-20180331.xsd#SignificantAccountingPoliciesNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SignificantAccountingPoliciesPolicies" xlink:href="tree-20180331.xsd#SignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/SignificantAccountingPoliciesTables" xlink:href="tree-20180331.xsd#SignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationDetailsChairmanAndChiefExecutiveOfficerGrants" xlink:href="tree-20180331.xsd#StockBasedCompensationDetailsChairmanAndChiefExecutiveOfficerGrants" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationDetailsPlImpact" xlink:href="tree-20180331.xsd#StockBasedCompensationDetailsPlImpact" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationDetailsRsaRsuRollforwards" xlink:href="tree-20180331.xsd#StockBasedCompensationDetailsRsaRsuRollforwards" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationDetailsRsusWithPerformanceConditions" xlink:href="tree-20180331.xsd#StockBasedCompensationDetailsRsusWithPerformanceConditions" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationDetailsStockOptionsRollforward" xlink:href="tree-20180331.xsd#StockBasedCompensationDetailsStockOptionsRollforward" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationNote" xlink:href="tree-20180331.xsd#StockBasedCompensationNote" xlink:type="simple" />
  <link:roleRef roleURI="http://www.tree.com/role/StockBasedCompensationTables" xlink:href="tree-20180331.xsd#StockBasedCompensationTables" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" xlink:type="simple" />
  <link:definitionLink xlink:role="http://www.tree.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetailsBalanceSheet" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/AccruedExpensesAndOtherCurrentLiabilitiesNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/BusinessAcquisitionDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_21A2614E3F9E52A239DA031FF4FFA34F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_21A2614E3F9E52A239DA031FF4FFA34F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_6B98FD9566755D5D6101031FF500E458" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_21A2614E3F9E52A239DA031FF4FFA34F" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_6B98FD9566755D5D6101031FF500E458" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_71BCF494BAEC0D3D22B4031FF500E401_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_6B98FD9566755D5D6101031FF500E458" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_71BCF494BAEC0D3D22B4031FF500E401_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_71BCF494BAEC0D3D22B4031FF500E401" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_6B98FD9566755D5D6101031FF500E458" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_71BCF494BAEC0D3D22B4031FF500E401" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_53A4B2D6F4F4D1D41D5A031FF500AFF3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_71BCF494BAEC0D3D22B4031FF500E401" xlink:to="loc_us-gaap_SubsequentEventMember_53A4B2D6F4F4D1D41D5A031FF500AFF3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_C4175D166DB3F92B7B68031FF5011B1E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_21A2614E3F9E52A239DA031FF4FFA34F" xlink:to="loc_us-gaap_RangeAxis_C4175D166DB3F92B7B68031FF5011B1E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_7ED6E1B48B13A517D11D031FF5015A7E_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_C4175D166DB3F92B7B68031FF5011B1E" xlink:to="loc_us-gaap_RangeMember_7ED6E1B48B13A517D11D031FF5015A7E_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_7ED6E1B48B13A517D11D031FF5015A7E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_C4175D166DB3F92B7B68031FF5011B1E" xlink:to="loc_us-gaap_RangeMember_7ED6E1B48B13A517D11D031FF5015A7E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_C88B23DADDAF469E3D91031FF50199B0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_7ED6E1B48B13A517D11D031FF5015A7E" xlink:to="loc_us-gaap_MinimumMember_C88B23DADDAF469E3D91031FF50199B0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_7F6E3A5BAFE8F2088E53031FF501FB4C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_7ED6E1B48B13A517D11D031FF5015A7E" xlink:to="loc_us-gaap_MaximumMember_7F6E3A5BAFE8F2088E53031FF501FB4C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContingentConsiderationByTypeAxis" xlink:label="loc_us-gaap_ContingentConsiderationByTypeAxis_57DA511040678929655A031FF5013D2F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_21A2614E3F9E52A239DA031FF4FFA34F" xlink:to="loc_us-gaap_ContingentConsiderationByTypeAxis_57DA511040678929655A031FF5013D2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContingentConsiderationTypeDomain" xlink:label="loc_us-gaap_ContingentConsiderationTypeDomain_E38219DF386D30D490B9031FF501D9CB_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContingentConsiderationByTypeAxis_57DA511040678929655A031FF5013D2F" xlink:to="loc_us-gaap_ContingentConsiderationTypeDomain_E38219DF386D30D490B9031FF501D9CB_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContingentConsiderationTypeDomain" xlink:label="loc_us-gaap_ContingentConsiderationTypeDomain_E38219DF386D30D490B9031FF501D9CB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContingentConsiderationByTypeAxis_57DA511040678929655A031FF5013D2F" xlink:to="loc_us-gaap_ContingentConsiderationTypeDomain_E38219DF386D30D490B9031FF501D9CB" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_EarnoutPaymentforOneContingentEarnoutMember" xlink:label="loc_tree_EarnoutPaymentforOneContingentEarnoutMember_A9F749CFFD607A2F8893031FF501FAF9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContingentConsiderationTypeDomain_E38219DF386D30D490B9031FF501D9CB" xlink:to="loc_tree_EarnoutPaymentforOneContingentEarnoutMember_A9F749CFFD607A2F8893031FF501FAF9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_BC366B9F2CF0BB51DCB1031FF5015F91" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_21A2614E3F9E52A239DA031FF4FFA34F" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_BC366B9F2CF0BB51DCB1031FF5015F91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_BC366B9F2CF0BB51DCB1031FF5015F91" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_BC366B9F2CF0BB51DCB1031FF5015F91" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_CompareCardsMember" xlink:label="loc_tree_CompareCardsMember_5B06ABFA2CC6FC270C44031FF5018069" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32" xlink:to="loc_tree_CompareCardsMember_5B06ABFA2CC6FC270C44031FF5018069" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_DepositAccountsMember" xlink:label="loc_tree_DepositAccountsMember_1FB95EF5952AB6E910D6031FF5014786" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32" xlink:to="loc_tree_DepositAccountsMember_1FB95EF5952AB6E910D6031FF5014786" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_SnapCapMember" xlink:label="loc_tree_SnapCapMember_4C87BC22B5E331750BF6031FF5012954" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_63B20C6FE332A77515AD031FF5015F32" xlink:to="loc_tree_SnapCapMember_4C87BC22B5E331750BF6031FF5012954" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_4C34F73242BBEDFAEBDB031FF501BAC6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_4C34F73242BBEDFAEBDB031FF501BAC6" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_BusinessCombinationNumberOfPayments" xlink:label="loc_tree_BusinessCombinationNumberOfPayments_C4651FE965A0A6ABF915031FF5022B3A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_tree_BusinessCombinationNumberOfPayments_C4651FE965A0A6ABF915031FF5022B3A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationIndemnificationAssetsRangeOfOutcomesValueLow" xlink:label="loc_us-gaap_BusinessCombinationIndemnificationAssetsRangeOfOutcomesValueLow_E76D36196B6687C530C2031FF5026738" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationIndemnificationAssetsRangeOfOutcomesValueLow_E76D36196B6687C530C2031FF5026738" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh_63D86853106626C555F2031FF50224E9" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesValueHigh_63D86853106626C555F2031FF50224E9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_F47229F633206B57FE47031FF50219ED" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_F47229F633206B57FE47031FF50219ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_7DE349E21753705F2971031FF502DA03" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_7DE349E21753705F2971031FF502DA03" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities" xlink:label="loc_us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_CEEB5613DDADDE0434FC031FF502D5AE" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_CEEB5613DDADDE0434FC031FF502D5AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_9F3A5F1FECD537B656B0031FF502DF0E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityCurrent_9F3A5F1FECD537B656B0031FF502DF0E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_A8286A90E834D1D2BF01031FF502B1EB" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_A8286A90E834D1D2BF01031FF502B1EB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_DA536F561FBCB21F02DC031FF502A4AB" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_DA536F561FBCB21F02DC031FF502A4AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities" xlink:label="loc_us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities_D005C089C47827C08308031FF502FA10" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_PaymentForContingentConsiderationLiabilityInvestingActivities_D005C089C47827C08308031FF502FA10" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_BusinessCombinationContingentConsiderationIndividualPaymentsBasedonSpecifiedIncreasesinFederalFundsInterestRates" xlink:label="loc_tree_BusinessCombinationContingentConsiderationIndividualPaymentsBasedonSpecifiedIncreasesinFederalFundsInterestRates_BE232DEEE5D3B0489376031FF502D939" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_tree_BusinessCombinationContingentConsiderationIndividualPaymentsBasedonSpecifiedIncreasesinFederalFundsInterestRates_BE232DEEE5D3B0489376031FF502D939" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_BusinessCombinationContingentConsiderationOneTimePerformancePayment" xlink:label="loc_tree_BusinessCombinationContingentConsiderationOneTimePerformancePayment_942D3BE192A56873D18E031FF502EF6A" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_tree_BusinessCombinationContingentConsiderationOneTimePerformancePayment_942D3BE192A56873D18E031FF502EF6A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionsProFormaRevenue" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaRevenue_08467C76C54876B52BF8031FF5021B65" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessAcquisitionsProFormaRevenue_08467C76C54876B52BF8031FF5021B65" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax_B6BF2896E4112501471D031FF5028E51" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_us-gaap_BusinessAcquisitionsProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTax_B6BF2896E4112501471D031FF5028E51" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_BusinessCombinationContingentConsiderationArrangementsAfterTaxContingentConsiderationExpense" xlink:label="loc_tree_BusinessCombinationContingentConsiderationArrangementsAfterTaxContingentConsiderationExpense_FF6D06F0B9D84E68E30A031FF502C37A" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_DE2ABD85021F41451EE6031FF501F40E" xlink:to="loc_tree_BusinessCombinationContingentConsiderationArrangementsAfterTaxContingentConsiderationExpense_FF6D06F0B9D84E68E30A031FF502C37A" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/BusinessAcquisitionNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/BusinessAcquisitionTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/CashAndRestrictedCashDetailsBalanceSheet" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_643D922D097D69ED2ACBFD6A1782D141" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable" xlink:label="loc_us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_E51A651B0AF430329F56FD6A1781BF0F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_643D922D097D69ED2ACBFD6A1782D141" xlink:to="loc_us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_E51A651B0AF430329F56FD6A1781BF0F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_D130D078F8000E97090AFD6A17821819" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestrictedCashAndCashEquivalentsTable_E51A651B0AF430329F56FD6A1781BF0F" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_D130D078F8000E97090AFD6A17821819" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_5414802E07D75528FD7AFD6A1782F04C_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_D130D078F8000E97090AFD6A17821819" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_5414802E07D75528FD7AFD6A1782F04C_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_5414802E07D75528FD7AFD6A1782F04C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsAxis_D130D078F8000E97090AFD6A17821819" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_5414802E07D75528FD7AFD6A1782F04C" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_EscrowDepositForSaleOfLTLMember" xlink:label="loc_tree_EscrowDepositForSaleOfLTLMember_34451D7CC18F6B8EFAB8FD6A17820FA3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_5414802E07D75528FD7AFD6A1782F04C" xlink:to="loc_tree_EscrowDepositForSaleOfLTLMember_34451D7CC18F6B8EFAB8FD6A17820FA3" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_OtherRestrictedCashAndCashEquivalentsMember" xlink:label="loc_tree_OtherRestrictedCashAndCashEquivalentsMember_FF243F12D37536F37F11FD6A17829067" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_5414802E07D75528FD7AFD6A1782F04C" xlink:to="loc_tree_OtherRestrictedCashAndCashEquivalentsMember_FF243F12D37536F37F11FD6A17829067" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_01DC209CFB018E04B287FD6A17833C48" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_643D922D097D69ED2ACBFD6A1782D141" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_01DC209CFB018E04B287FD6A17833C48" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_ECA1EE048D4F33298906FD6A1782DA3E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_643D922D097D69ED2ACBFD6A1782D141" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_ECA1EE048D4F33298906FD6A1782DA3E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_C6368D28BC70F9BF077EFD6C8EC8DEFE" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsItemsLineItems_643D922D097D69ED2ACBFD6A1782D141" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_C6368D28BC70F9BF077EFD6C8EC8DEFE" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/CashAndRestrictedCashNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/CashAndRestrictedCashTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/ConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_44529E341E7237D5FF38038F69433A06" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_BFE6DFB749AAA14D04E8038F69439E82" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_44529E341E7237D5FF38038F69433A06" xlink:to="loc_us-gaap_StatementTable_BFE6DFB749AAA14D04E8038F69439E82" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_BBFB3A47255B3C1B5049038F6943814E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_BFE6DFB749AAA14D04E8038F69439E82" xlink:to="loc_us-gaap_StatementScenarioAxis_BBFB3A47255B3C1B5049038F6943814E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_B31D9B42321ED4E31002038F69432564_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_BBFB3A47255B3C1B5049038F6943814E" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_B31D9B42321ED4E31002038F69432564_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_B31D9B42321ED4E31002038F69432564" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_BBFB3A47255B3C1B5049038F6943814E" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_B31D9B42321ED4E31002038F69432564" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_7E035F883803FA2CA63B038F69430E1F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_BFE6DFB749AAA14D04E8038F69439E82" xlink:to="loc_us-gaap_StatementClassOfStockAxis_7E035F883803FA2CA63B038F69430E1F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_852E9CA0AE90AD69CB40038F69438E95_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_7E035F883803FA2CA63B038F69430E1F" xlink:to="loc_us-gaap_ClassOfStockDomain_852E9CA0AE90AD69CB40038F69438E95_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_852E9CA0AE90AD69CB40038F69438E95" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_7E035F883803FA2CA63B038F69430E1F" xlink:to="loc_us-gaap_ClassOfStockDomain_852E9CA0AE90AD69CB40038F69438E95" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/ConsolidatedStatementOfShareholdersEquity" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_843B0CFEB5972618AF05F7E1B61E13C9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_E2B8F2AFCC2711DED175F7E1B61EF451" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_843B0CFEB5972618AF05F7E1B61E13C9" xlink:to="loc_us-gaap_StatementTable_E2B8F2AFCC2711DED175F7E1B61EF451" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_7951C60F09CCC0C81223F7E1B61EC3EA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_E2B8F2AFCC2711DED175F7E1B61EF451" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_7951C60F09CCC0C81223F7E1B61EC3EA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_7951C60F09CCC0C81223F7E1B61EC3EA" xlink:to="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_7951C60F09CCC0C81223F7E1B61EC3EA" xlink:to="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_647E4473573747E9CBF5F7E1B61E4940" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:to="loc_us-gaap_CommonStockMember_647E4473573747E9CBF5F7E1B61E4940" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_AB2137583CFC27C8A675F7E1B61E3E21" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_AB2137583CFC27C8A675F7E1B61E3E21" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_83FACA5F7ECFEE1B144EF7E1B61E69BB" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:to="loc_us-gaap_RetainedEarningsMember_83FACA5F7ECFEE1B144EF7E1B61E69BB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_FBD183A6413030AE6942F7E1B61E2707" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:to="loc_us-gaap_TreasuryStockMember_FBD183A6413030AE6942F7E1B61E2707" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ComprehensiveIncomeMember" xlink:label="loc_us-gaap_ComprehensiveIncomeMember_CC4547444DF8B160BC86F7E1B61E9A94" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:to="loc_us-gaap_ComprehensiveIncomeMember_CC4547444DF8B160BC86F7E1B61E9A94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember_20E2B51890E2F813D7E0F7E1B61EE1E1" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0CEC3859B62DE17FA83DF7E1B61ED589" xlink:to="loc_us-gaap_NoncontrollingInterestMember_20E2B51890E2F813D7E0F7E1B61EE1E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_843B0CFEB5972618AF05F7E1B61E13C9" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_A7171B1C001A090A911FF7E1B61EE059" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_StockholdersEquity_A7171B1C001A090A911FF7E1B61EE059" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaap_SharesIssued_72F2631E63DADABEC8B0F7E1B61E3C28" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_SharesIssued_72F2631E63DADABEC8B0F7E1B61E3C28" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_8CCCF9BE37126AC58331F7E1B61EA3AA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_8CCCF9BE37126AC58331F7E1B61EA3AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_8025796F66FE7FD0C1F6F7E1B61ED7BB" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_8025796F66FE7FD0C1F6F7E1B61ED7BB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TreasuryStockSharesAcquired" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_5318A3C939FB27344D9EF7E1B61E6555" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_5318A3C939FB27344D9EF7E1B61E6555" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_9DEA5A5CB317B07189F7F7E1B61E20C3" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_9DEA5A5CB317B07189F7F7E1B61E20C3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_82020BAA44670BBEC874F7E1B61E5E5F" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_82020BAA44670BBEC874F7E1B61E5E5F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_64A431C4749556863588F7E1B61EB05D" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_64A431C4749556863588F7E1B61EB05D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification" xlink:label="loc_us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification_257C93169C845AD3DAECF80131E1F886" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification_257C93169C845AD3DAECF80131E1F886" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_385B5360D55451CFD26FF7E1B61E394C" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_415529F8782AC32E6FC8F7E1B61E8C2D" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_385B5360D55451CFD26FF7E1B61E394C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/ConsolidatedStatementsOfCashFlows" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_AC846018993328A40D9E038F692F966C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_0FF673069DAB2C2D615B038F692F55C4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_AC846018993328A40D9E038F692F966C" xlink:to="loc_us-gaap_StatementTable_0FF673069DAB2C2D615B038F692F55C4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_2DCDC0D49DE258281ABC038F692FFDAC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_0FF673069DAB2C2D615B038F692F55C4" xlink:to="loc_us-gaap_StatementScenarioAxis_2DCDC0D49DE258281ABC038F692FFDAC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_4BFEDAF79A2DDBA08C54038F692F8881_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_2DCDC0D49DE258281ABC038F692FFDAC" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_4BFEDAF79A2DDBA08C54038F692F8881_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_4BFEDAF79A2DDBA08C54038F692F8881" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_2DCDC0D49DE258281ABC038F692FFDAC" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_4BFEDAF79A2DDBA08C54038F692F8881" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/ConsolidatedStatementsOfOperationsAndComprehensiveIncome" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_401CA193A2A3B30F6AA0038EE83ABF28" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_StatementTable_401CA193A2A3B30F6AA0038EE83ABF28" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_CDC06E2C0CCD8D7047AA038EE83B2E3B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_401CA193A2A3B30F6AA0038EE83ABF28" xlink:to="loc_us-gaap_StatementScenarioAxis_CDC06E2C0CCD8D7047AA038EE83B2E3B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_C11332F60B78EB1AC7ED038EE83B78E3_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_CDC06E2C0CCD8D7047AA038EE83B2E3B" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_C11332F60B78EB1AC7ED038EE83B78E3_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_C11332F60B78EB1AC7ED038EE83B78E3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_CDC06E2C0CCD8D7047AA038EE83B2E3B" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_C11332F60B78EB1AC7ED038EE83B78E3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_3EB53445E58F10DB4F7C038EE83C1740" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_Revenues_3EB53445E58F10DB4F7C038EE83C1740" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostsAndExpensesAbstract" xlink:label="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaap_CostOfRevenue_9C535037618AB421160B038EE83E9550" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_CostOfRevenue_9C535037618AB421160B038EE83E9550" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaap_SellingAndMarketingExpense_D73912436FE3A402F97D038EE83E35D1" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_SellingAndMarketingExpense_D73912436FE3A402F97D038EE83E35D1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_F2BCBDEEE46FAD2AC016038EE83ED0FC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_F2BCBDEEE46FAD2AC016038EE83ED0FC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_8531149DAF9F7D042A04038EE83E5616" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_8531149DAF9F7D042A04038EE83E5616" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_980AA46C4A4ED10D6F5E038EE83E6DBA" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_980AA46C4A4ED10D6F5E038EE83E6DBA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_6B8CBEB3513A192834E1038EE83EA930" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_6B8CBEB3513A192834E1038EE83EA930" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_7ECF4B9DE383277D7022038EE83ED10D" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_7ECF4B9DE383277D7022038EE83ED10D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SeveranceCosts1" xlink:label="loc_us-gaap_SeveranceCosts1_11E3BBF2BAF08C002B35038EE83EFDC3" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_SeveranceCosts1_11E3BBF2BAF08C002B35038EE83EFDC3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationSettlementExpense" xlink:label="loc_us-gaap_LitigationSettlementExpense_BA65EA8EB535F9DE231D038EE83E0EEC" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_LitigationSettlementExpense_BA65EA8EB535F9DE231D038EE83E0EEC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostsAndExpenses" xlink:label="loc_us-gaap_CostsAndExpenses_C4D6EE07654881E1AB31038EE83E70A2" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_DB63E82D40A519BFA888038EE83E907F" xlink:to="loc_us-gaap_CostsAndExpenses_C4D6EE07654881E1AB31038EE83E70A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_698DDD07FC9CF796DBEE038EE83EF5B7" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_OperatingIncomeLoss_698DDD07FC9CF796DBEE038EE83EF5B7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpenseAbstract_7347E0F7CCDCCB14E8E3038EE83F76E2" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpenseAbstract_7347E0F7CCDCCB14E8E3038EE83F76E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="loc_us-gaap_InterestIncomeExpenseNet_48C45002E5A1A7845B3F038EE83FABE9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpenseAbstract_7347E0F7CCDCCB14E8E3038EE83F76E2" xlink:to="loc_us-gaap_InterestIncomeExpenseNet_48C45002E5A1A7845B3F038EE83FABE9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_AAA1795997F2A1EF1141038EE83F562A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpenseAbstract_7347E0F7CCDCCB14E8E3038EE83F76E2" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_AAA1795997F2A1EF1141038EE83F562A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_B3FF7E5DE08275E48A42038EE83F15F3" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_B3FF7E5DE08275E48A42038EE83F15F3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_96C98735244DED63F7E6038EE83FA48D" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_96C98735244DED63F7E6038EE83FA48D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperations" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_96F64DD5A748557FC9BB038EE83F0B8B" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperations_96F64DD5A748557FC9BB038EE83F0B8B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_DA5D91DCA741ED621E7C038EE83F73D5" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_DA5D91DCA741ED621E7C038EE83F73D5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E02BCFF744AFD5988CE9038EE83FC4B2" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_E02BCFF744AFD5988CE9038EE83FC4B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_090B7B49469C191746CF038EE83F9231" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_090B7B49469C191746CF038EE83F9231" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_0B7859EE3F79B1B14CA2038EE83FAD16" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_090B7B49469C191746CF038EE83F9231" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_0B7859EE3F79B1B14CA2038EE83FAD16" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_9298228B83C92ED0BEE5038EE83F32C4" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_090B7B49469C191746CF038EE83F9231" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_9298228B83C92ED0BEE5038EE83F32C4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasicAndDilutedAbstract" xlink:label="loc_us-gaap_EarningsPerShareBasicAndDilutedAbstract_E1D391DAABD6FD08E9DF038EE83F8FB3" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_EarningsPerShareBasicAndDilutedAbstract_E1D391DAABD6FD08E9DF038EE83F8FB3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_A6CDA7CEB547964CBF96038EE83FF1CF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicAndDilutedAbstract_E1D391DAABD6FD08E9DF038EE83F8FB3" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_A6CDA7CEB547964CBF96038EE83FF1CF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_A17CF32D7991C4DB9048038EE83FB9CD" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicAndDilutedAbstract_E1D391DAABD6FD08E9DF038EE83F8FB3" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_A17CF32D7991C4DB9048038EE83FB9CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract_8838847BEC0BF7F01BD1038EE83F5F1E" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract_8838847BEC0BF7F01BD1038EE83F5F1E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_AE82F950D432E1475122038EE83F6D13" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract_8838847BEC0BF7F01BD1038EE83F5F1E" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_AE82F950D432E1475122038EE83F6D13" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_F80F9C3CE1255E452865038EE83F0919" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeLossFromDiscontinuedOperationsAndDisposalOfDiscontinuedOperationsNetOfTaxPerBasicAndDilutedShareAbstract_8838847BEC0BF7F01BD1038EE83F5F1E" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_F80F9C3CE1255E452865038EE83F0919" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_39F9614C24423F34A695038EE83F52E4" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_8253C190B5933DEA91BE038EE83B80B1" xlink:to="loc_us-gaap_EarningsPerShareAbstract_39F9614C24423F34A695038EE83F52E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_CC51C9BDE92EBB8A7D09038EE8409DA6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_39F9614C24423F34A695038EE83F52E4" xlink:to="loc_us-gaap_EarningsPerShareBasic_CC51C9BDE92EBB8A7D09038EE8409DA6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_E6C16AD552A846DAC355038EE840A476" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_39F9614C24423F34A695038EE83F52E4" xlink:to="loc_us-gaap_EarningsPerShareDiluted_E6C16AD552A846DAC355038EE840A476" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/ContingenciesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingenciesLineItems" xlink:label="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingenciesTable" xlink:label="loc_us-gaap_LossContingenciesTable_457D2B5E9659127FA02DFD6D5E454484" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_us-gaap_LossContingenciesTable_457D2B5E9659127FA02DFD6D5E454484" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_E96D683DBC161ABDCA85FD6D5E457886" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_457D2B5E9659127FA02DFD6D5E454484" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_E96D683DBC161ABDCA85FD6D5E457886" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_BD59CD9E2D763AEB1D86FD6D5E46306D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_E96D683DBC161ABDCA85FD6D5E457886" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_BD59CD9E2D763AEB1D86FD6D5E46306D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_BD59CD9E2D763AEB1D86FD6D5E46306D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_E96D683DBC161ABDCA85FD6D5E457886" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_BD59CD9E2D763AEB1D86FD6D5E46306D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DiscontinuedOperationsDisposedOfBySaleMember" xlink:label="loc_us-gaap_DiscontinuedOperationsDisposedOfBySaleMember_96CFA134D8F7EEF321CDFD6D5E468683" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_BD59CD9E2D763AEB1D86FD6D5E46306D" xlink:to="loc_us-gaap_DiscontinuedOperationsDisposedOfBySaleMember_96CFA134D8F7EEF321CDFD6D5E468683" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_93926E17370C71FDA0A2FD6D5E461E1E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_457D2B5E9659127FA02DFD6D5E454484" xlink:to="loc_us-gaap_RangeAxis_93926E17370C71FDA0A2FD6D5E461E1E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_4A319A212698C4886D72FD6D5E46FEA0_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_93926E17370C71FDA0A2FD6D5E461E1E" xlink:to="loc_us-gaap_RangeMember_4A319A212698C4886D72FD6D5E46FEA0_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_4A319A212698C4886D72FD6D5E46FEA0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_93926E17370C71FDA0A2FD6D5E461E1E" xlink:to="loc_us-gaap_RangeMember_4A319A212698C4886D72FD6D5E46FEA0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_D5F1D5A046987925FACDFD6D5E4649E1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_4A319A212698C4886D72FD6D5E46FEA0" xlink:to="loc_us-gaap_MinimumMember_D5F1D5A046987925FACDFD6D5E4649E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_45E4ABE25AF5B2D85D5CFD6D5E46D889" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_4A319A212698C4886D72FD6D5E46FEA0" xlink:to="loc_us-gaap_MaximumMember_45E4ABE25AF5B2D85D5CFD6D5E46D889" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationStatusAxis" xlink:label="loc_us-gaap_LitigationStatusAxis_45473DE8A93DD8505478FD6D5E469DC8" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_457D2B5E9659127FA02DFD6D5E454484" xlink:to="loc_us-gaap_LitigationStatusAxis_45473DE8A93DD8505478FD6D5E469DC8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationStatusDomain" xlink:label="loc_us-gaap_LitigationStatusDomain_E04B882A593BE879FA22FD6D5E46F5E5_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LitigationStatusAxis_45473DE8A93DD8505478FD6D5E469DC8" xlink:to="loc_us-gaap_LitigationStatusDomain_E04B882A593BE879FA22FD6D5E46F5E5_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationStatusDomain" xlink:label="loc_us-gaap_LitigationStatusDomain_E04B882A593BE879FA22FD6D5E46F5E5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LitigationStatusAxis_45473DE8A93DD8505478FD6D5E469DC8" xlink:to="loc_us-gaap_LitigationStatusDomain_E04B882A593BE879FA22FD6D5E46F5E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PendingLitigationMember" xlink:label="loc_us-gaap_PendingLitigationMember_0BB8D96E75EB8C50A3F4FD6D5E46B343" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LitigationStatusDomain_E04B882A593BE879FA22FD6D5E46F5E5" xlink:to="loc_us-gaap_PendingLitigationMember_0BB8D96E75EB8C50A3F4FD6D5E46B343" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationCaseAxis" xlink:label="loc_us-gaap_LitigationCaseAxis_B9C02728C76270CAF638FD6D5E4696B4" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_457D2B5E9659127FA02DFD6D5E454484" xlink:to="loc_us-gaap_LitigationCaseAxis_B9C02728C76270CAF638FD6D5E4696B4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationCaseTypeDomain" xlink:label="loc_us-gaap_LitigationCaseTypeDomain_9C41AF0D0B53C40AA42AFD6D5E4604CC_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LitigationCaseAxis_B9C02728C76270CAF638FD6D5E4696B4" xlink:to="loc_us-gaap_LitigationCaseTypeDomain_9C41AF0D0B53C40AA42AFD6D5E4604CC_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationCaseTypeDomain" xlink:label="loc_us-gaap_LitigationCaseTypeDomain_9C41AF0D0B53C40AA42AFD6D5E4604CC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LitigationCaseAxis_B9C02728C76270CAF638FD6D5E4696B4" xlink:to="loc_us-gaap_LitigationCaseTypeDomain_9C41AF0D0B53C40AA42AFD6D5E4604CC" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ResidentialFundingCompanyDomain" xlink:label="loc_tree_ResidentialFundingCompanyDomain_278256A9165A5FB05D19FD6D5E47B0A5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LitigationCaseTypeDomain_9C41AF0D0B53C40AA42AFD6D5E4604CC" xlink:to="loc_tree_ResidentialFundingCompanyDomain_278256A9165A5FB05D19FD6D5E47B0A5" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LehmanBrothersHoldingsInc.DemandLetterMember" xlink:label="loc_tree_LehmanBrothersHoldingsInc.DemandLetterMember_0A5E4A0C738FC7B3D1C0FD6D5E472A84" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LitigationCaseTypeDomain_9C41AF0D0B53C40AA42AFD6D5E4604CC" xlink:to="loc_tree_LehmanBrothersHoldingsInc.DemandLetterMember_0A5E4A0C738FC7B3D1C0FD6D5E472A84" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LitigationReserve" xlink:label="loc_us-gaap_LitigationReserve_D96A44AB9305F23C2A0CFD6D5E473CE6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_us-gaap_LitigationReserve_D96A44AB9305F23C2A0CFD6D5E473CE6" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingencyNumberOfLoanOriginators" xlink:label="loc_tree_LossContingencyNumberOfLoanOriginators_986AEA0E202852584AE0FDCDF1F6507D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_tree_LossContingencyNumberOfLoanOriginators_986AEA0E202852584AE0FDCDF1F6507D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyPendingClaimsNumber" xlink:label="loc_us-gaap_LossContingencyPendingClaimsNumber_038D8F60D70253D1E6E0FDCBD1AEF8D0" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_us-gaap_LossContingencyPendingClaimsNumber_038D8F60D70253D1E6E0FDCBD1AEF8D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyDamagesSoughtValue" xlink:label="loc_us-gaap_LossContingencyDamagesSoughtValue_B5452E65A134C4C2F19BFDC9B4FFA060" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_us-gaap_LossContingencyDamagesSoughtValue_B5452E65A134C4C2F19BFDC9B4FFA060" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyNumberOfDefendants" xlink:label="loc_us-gaap_LossContingencyNumberOfDefendants_097EA98FD873DC1FC306FDD002211B4A" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_us-gaap_LossContingencyNumberOfDefendants_097EA98FD873DC1FC306FDD002211B4A" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingencyNumberOfLoans" xlink:label="loc_tree_LossContingencyNumberOfLoans_C906F4D8F762FDD66BA1FDD38EBE30A4" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5F9C587C61A9D62CC8FDFD6D5E47D511" xlink:to="loc_tree_LossContingencyNumberOfLoans_C906F4D8F762FDD66BA1FDD38EBE30A4" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/ContingenciesNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/DebtDetailsConvertibleNoteHedgeAndWarrantTransactions" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_264B2F77035F2F911A78FD6D5E658BE7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_264B2F77035F2F911A78FD6D5E658BE7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_5FE658CC67B78DD5A6C4FD6D5E6509A2_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_264B2F77035F2F911A78FD6D5E658BE7" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_5FE658CC67B78DD5A6C4FD6D5E6509A2_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_5FE658CC67B78DD5A6C4FD6D5E6509A2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_264B2F77035F2F911A78FD6D5E658BE7" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_5FE658CC67B78DD5A6C4FD6D5E6509A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_9C3167F43F43B4BBBE2BFD6D5E66E2FE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:to="loc_us-gaap_DebtInstrumentAxis_9C3167F43F43B4BBBE2BFD6D5E66E2FE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_7D173C1892082407E647FD6D5E6663B4_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_9C3167F43F43B4BBBE2BFD6D5E66E2FE" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_7D173C1892082407E647FD6D5E6663B4_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_7D173C1892082407E647FD6D5E6663B4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_9C3167F43F43B4BBBE2BFD6D5E66E2FE" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_7D173C1892082407E647FD6D5E6663B4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_1DD8ACCC97B8EC677573FD6D5E664146" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:to="loc_us-gaap_VariableRateAxis_1DD8ACCC97B8EC677573FD6D5E664146" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_9ECDDAD36C746B502EF3FD6D5E6688A1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_1DD8ACCC97B8EC677573FD6D5E664146" xlink:to="loc_us-gaap_VariableRateDomain_9ECDDAD36C746B502EF3FD6D5E6688A1_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_9ECDDAD36C746B502EF3FD6D5E6688A1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_1DD8ACCC97B8EC677573FD6D5E664146" xlink:to="loc_us-gaap_VariableRateDomain_9ECDDAD36C746B502EF3FD6D5E6688A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodAxis" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_93F86337FF94047DA31AFD6D5E66B81D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_93F86337FF94047DA31AFD6D5E66B81D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_50650F4D8A8A6C1A4282FD6D5E6655BF_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_93F86337FF94047DA31AFD6D5E66B81D" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_50650F4D8A8A6C1A4282FD6D5E6655BF_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_50650F4D8A8A6C1A4282FD6D5E6655BF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_93F86337FF94047DA31AFD6D5E66B81D" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_50650F4D8A8A6C1A4282FD6D5E6655BF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_8122D3091CE05A4E6703FD6D5E66DA27" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_914E3805E63BA58DB0EFFD6D5E653219" xlink:to="loc_us-gaap_RangeAxis_8122D3091CE05A4E6703FD6D5E66DA27" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_49BAAF1DAE9AA11859D5FD6D5E667C12_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_8122D3091CE05A4E6703FD6D5E66DA27" xlink:to="loc_us-gaap_RangeMember_49BAAF1DAE9AA11859D5FD6D5E667C12_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_49BAAF1DAE9AA11859D5FD6D5E667C12" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_8122D3091CE05A4E6703FD6D5E66DA27" xlink:to="loc_us-gaap_RangeMember_49BAAF1DAE9AA11859D5FD6D5E667C12" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_NetproceedsfromtheConvertibleNotesusedtopayforthecostoftheConvertibleNoteHedge" xlink:label="loc_tree_NetproceedsfromtheConvertibleNotesusedtopayforthecostoftheConvertibleNoteHedge_CB260EC1B7C90E576FD0FD6D5E67909A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_tree_NetproceedsfromtheConvertibleNotesusedtopayforthecostoftheConvertibleNoteHedge_CB260EC1B7C90E576FD0FD6D5E67909A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsForHedgeFinancingActivities" xlink:label="loc_us-gaap_PaymentsForHedgeFinancingActivities_9A0C36215E9D7D9F3407FD6D5E671A71" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_us-gaap_PaymentsForHedgeFinancingActivities_9A0C36215E9D7D9F3407FD6D5E671A71" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_NumberofSharesCoveredbytheHedgeTransactions" xlink:label="loc_tree_NumberofSharesCoveredbytheHedgeTransactions_142BB140171496B4E6ABFD6D5E67AB9B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_tree_NumberofSharesCoveredbytheHedgeTransactions_142BB140171496B4E6ABFD6D5E67AB9B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_59DD84A28C5BB5347CBEFD6D5E67F601" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_59DD84A28C5BB5347CBEFD6D5E67F601" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_AF219AF93018BA3CCE37FD6D5E672EFE" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_AF219AF93018BA3CCE37FD6D5E672EFE" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_Premiumofwarrantstrikepriceoversalespriceofcommonstock" xlink:label="loc_tree_Premiumofwarrantstrikepriceoversalespriceofcommonstock_2863B920ACF751FC9E82FD6D5E67F7A4" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_tree_Premiumofwarrantstrikepriceoversalespriceofcommonstock_2863B920ACF751FC9E82FD6D5E67F7A4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaap_SharePrice_F737831B5BD82EC862FBFD6D5E6705AE" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_us-gaap_SharePrice_F737831B5BD82EC862FBFD6D5E6705AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromIssuanceOfWarrants" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfWarrants_13084E84BB9617960E54FD6D5E67E56E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CEC41B9AA4740AAC5529FD6D5E66C619" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfWarrants_13084E84BB9617960E54FD6D5E67E56E" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/DebtDetailsConvertibleSeniorNotes" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_6A1710F234EF393A66D2FD6D5E71447A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentTable_6A1710F234EF393A66D2FD6D5E71447A" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_D8540B90B5E8D4BA5CAFFD6D5E7504FC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_6A1710F234EF393A66D2FD6D5E71447A" xlink:to="loc_us-gaap_DebtInstrumentAxis_D8540B90B5E8D4BA5CAFFD6D5E7504FC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_6FDD0CAAF2D550739D5EFD6D5E755BD5_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_D8540B90B5E8D4BA5CAFFD6D5E7504FC" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_6FDD0CAAF2D550739D5EFD6D5E755BD5_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_6FDD0CAAF2D550739D5EFD6D5E755BD5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_D8540B90B5E8D4BA5CAFFD6D5E7504FC" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_6FDD0CAAF2D550739D5EFD6D5E755BD5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConvertibleNotesPayableMember" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_937634CAB87F922C11CEFD6D5E758FE1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6FDD0CAAF2D550739D5EFD6D5E755BD5" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_937634CAB87F922C11CEFD6D5E758FE1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConvertibleDebt" xlink:label="loc_us-gaap_ConvertibleDebt_84A37AB0B1E2CB7CABDBFD6D5E76896A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_ConvertibleDebt_84A37AB0B1E2CB7CABDBFD6D5E76896A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_9CA0B700E7809D1151ADFD6D5E76F093" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_9CA0B700E7809D1151ADFD6D5E76F093" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_DebtConversionNumberofSharesofCommonStockConvertibleper1000ofPrincipalNotes" xlink:label="loc_tree_DebtConversionNumberofSharesofCommonStockConvertibleper1000ofPrincipalNotes_D9560B5FE834D7761729FD6D5E7619E2" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_tree_DebtConversionNumberofSharesofCommonStockConvertibleper1000ofPrincipalNotes_D9560B5FE834D7761729FD6D5E7619E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConvertiblePreferredStockTermsOfConversion" xlink:label="loc_us-gaap_ConvertiblePreferredStockTermsOfConversion_2F6B6003720C1DEDA3B5FD6D5E76B529" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_ConvertiblePreferredStockTermsOfConversion_2F6B6003720C1DEDA3B5FD6D5E76B529" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_72EEF8F62C1EE4DC287EFD6D5E762282" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_72EEF8F62C1EE4DC287EFD6D5E762282" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_D0714113B3C41D5824F6FD6D5E76C1C6" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_D0714113B3C41D5824F6FD6D5E76C1C6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentConvertibleThresholdTradingDays" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdTradingDays_FC0407AE2B576A071C4AFDBF22704415" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdTradingDays_FC0407AE2B576A071C4AFDBF22704415" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_6519F939ECC529A73CCFFDBF72494B6D" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_6519F939ECC529A73CCFFDBF72494B6D" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTriggerFiveBusinessDays" xlink:label="loc_tree_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTriggerFiveBusinessDays_BF504180409475A8E423FDC1C490DE65" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_tree_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTriggerFiveBusinessDays_BF504180409475A8E423FDC1C490DE65" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_AA7F67761B7573A0456CFD6D5E7783A5" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_AA7F67761B7573A0456CFD6D5E7783A5" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_NonconvertibleDebtBorrowingRateattheDateofIssuance" xlink:label="loc_tree_NonconvertibleDebtBorrowingRateattheDateofIssuance_D72687D8F541304E7A8CFD6D5E7737F3" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_tree_NonconvertibleDebtBorrowingRateattheDateofIssuance_D72687D8F541304E7A8CFD6D5E7737F3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConvertibleDebtNoncurrent" xlink:label="loc_us-gaap_ConvertibleDebtNoncurrent_0614E789D2553C2E3468FD6D5E77A104" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_ConvertibleDebtNoncurrent_0614E789D2553C2E3468FD6D5E77A104" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent" xlink:label="loc_us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent_6048602473263541BDBAFD6D5E771A91" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent_6048602473263541BDBAFD6D5E771A91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFinanceCostsGross" xlink:label="loc_us-gaap_DeferredFinanceCostsGross_05D000BE2C54C8F89255FD6D5E772D2A" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DeferredFinanceCostsGross_05D000BE2C54C8F89255FD6D5E772D2A" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_Debtissuancecostsliabilitycomponent" xlink:label="loc_tree_Debtissuancecostsliabilitycomponent_DBB11479A222D6BF7267FD6D5E77CB86" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_tree_Debtissuancecostsliabilitycomponent_DBB11479A222D6BF7267FD6D5E77CB86" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_Debtissuancecostsequitycomponent" xlink:label="loc_tree_Debtissuancecostsequitycomponent_38D9EFD6D58E78B71A6AFD6D5E78B938" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_tree_Debtissuancecostsequitycomponent_38D9EFD6D58E78B71A6AFD6D5E78B938" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="loc_us-gaap_InterestExpenseDebt_41BFD87B95078795DC0EFD6D5E785312" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_InterestExpenseDebt_41BFD87B95078795DC0EFD6D5E785312" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestExpenseDebtExcludingAmortization" xlink:label="loc_us-gaap_InterestExpenseDebtExcludingAmortization_3C1FB4017437E45E2C86FD6D5E783049" xlink:type="locator" />
    <link:definitionArc order="18" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_InterestExpenseDebtExcludingAmortization_3C1FB4017437E45E2C86FD6D5E783049" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfDebtDiscountPremium" xlink:label="loc_us-gaap_AmortizationOfDebtDiscountPremium_FC3061634B7B678B7E54FD6D5E786759" xlink:type="locator" />
    <link:definitionArc order="19" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_AmortizationOfDebtDiscountPremium_FC3061634B7B678B7E54FD6D5E786759" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_F4AC71A9DBDAF359DBBEFD6D5E78DFF5" xlink:type="locator" />
    <link:definitionArc order="20" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_F4AC71A9DBDAF359DBBEFD6D5E78DFF5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_986821D1C90345337365FD6D5E784C2B" xlink:type="locator" />
    <link:definitionArc order="21" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_986821D1C90345337365FD6D5E784C2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtFairValue" xlink:label="loc_us-gaap_LongTermDebtFairValue_C2554C0589651DDEBAEEFD6D5E78D689" xlink:type="locator" />
    <link:definitionArc order="22" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_LongTermDebtFairValue_C2554C0589651DDEBAEEFD6D5E78D689" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscount_DFD084C1663D5749C0DFFD6D5E780B45" xlink:type="locator" />
    <link:definitionArc order="23" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_AD448D859474113AFB1FFD6D5E7690A8" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscount_DFD084C1663D5749C0DFFD6D5E780B45" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/DebtDetailsRevolvingCreditFacility" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityTable" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_849AFFBCE5CADAAE7710FD6D5E570B3E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_us-gaap_LineOfCreditFacilityTable_849AFFBCE5CADAAE7710FD6D5E570B3E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_0E57F6BE8A7276F83B01FD6D5E588288" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_849AFFBCE5CADAAE7710FD6D5E570B3E" xlink:to="loc_us-gaap_RangeAxis_0E57F6BE8A7276F83B01FD6D5E588288" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_DEEB128E8E48F555BB58FD6D5E58EAF5_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_0E57F6BE8A7276F83B01FD6D5E588288" xlink:to="loc_us-gaap_RangeMember_DEEB128E8E48F555BB58FD6D5E58EAF5_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_DEEB128E8E48F555BB58FD6D5E58EAF5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_0E57F6BE8A7276F83B01FD6D5E588288" xlink:to="loc_us-gaap_RangeMember_DEEB128E8E48F555BB58FD6D5E58EAF5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_8C2E8CBA9B627BE37BAFFD6D5E589B39" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_DEEB128E8E48F555BB58FD6D5E58EAF5" xlink:to="loc_us-gaap_MinimumMember_8C2E8CBA9B627BE37BAFFD6D5E589B39" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_CA67943D960C3606A082FD6D5E58EE9D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_DEEB128E8E48F555BB58FD6D5E58EAF5" xlink:to="loc_us-gaap_MaximumMember_CA67943D960C3606A082FD6D5E58EE9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_56C958853030C9D0E910FD6D5E58CF94" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_849AFFBCE5CADAAE7710FD6D5E570B3E" xlink:to="loc_us-gaap_VariableRateAxis_56C958853030C9D0E910FD6D5E58CF94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_56C958853030C9D0E910FD6D5E58CF94" xlink:to="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_56C958853030C9D0E910FD6D5E58CF94" xlink:to="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FederalFundsEffectiveSwapRateMember" xlink:label="loc_us-gaap_FederalFundsEffectiveSwapRateMember_5621344767FC368E6DB3FD6D5E58884A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC" xlink:to="loc_us-gaap_FederalFundsEffectiveSwapRateMember_5621344767FC368E6DB3FD6D5E58884A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_ACF6A8E85FCBABFDDE16FD6D5E58F9D6" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC" xlink:to="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_ACF6A8E85FCBABFDDE16FD6D5E58F9D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BaseRateMember" xlink:label="loc_us-gaap_BaseRateMember_35DBB10779D7B9562635FD6D5E583216" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_9BCE712B2EAFFBE4FC67FD6D5E58B0CC" xlink:to="loc_us-gaap_BaseRateMember_35DBB10779D7B9562635FD6D5E583216" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_3C84A97C774208C715CFFD6D5E58934E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_849AFFBCE5CADAAE7710FD6D5E570B3E" xlink:to="loc_us-gaap_CreditFacilityAxis_3C84A97C774208C715CFFD6D5E58934E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_3C84A97C774208C715CFFD6D5E58934E" xlink:to="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_3C84A97C774208C715CFFD6D5E58934E" xlink:to="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_6AA06A54CE9DB14F2243FD6D5E588976" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_6AA06A54CE9DB14F2243FD6D5E588976" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_SwinglineFacilityMember" xlink:label="loc_tree_SwinglineFacilityMember_9E75F901A2252891FF71FD6D5E5805EB" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87" xlink:to="loc_tree_SwinglineFacilityMember_9E75F901A2252891FF71FD6D5E5805EB" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LettersofCreditMember" xlink:label="loc_tree_LettersofCreditMember_E59AEB272AEFCD4FD9C1FD6D5E585300" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_01F97A877C3E67073C3CFD6D5E58AC87" xlink:to="loc_tree_LettersofCreditMember_E59AEB272AEFCD4FD9C1FD6D5E585300" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_2A24EA303CAF8BC59765FD6D5E591DC9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_2A24EA303CAF8BC59765FD6D5E591DC9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_1FE781CC0BB33CA25F0CFD6D5E5962DE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_us-gaap_DebtInstrumentTerm_1FE781CC0BB33CA25F0CFD6D5E5962DE" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityConditionalIncreasetoBorrowingCapacity" xlink:label="loc_tree_LineofCreditFacilityConditionalIncreasetoBorrowingCapacity_8B517FF7D93EB2A545F0FD6D5E594182" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityConditionalIncreasetoBorrowingCapacity_8B517FF7D93EB2A545F0FD6D5E594182" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_RatioofDebttoEBITDAtoIncreaseRevolvingCommitment" xlink:label="loc_tree_RatioofDebttoEBITDAtoIncreaseRevolvingCommitment_0A652664CEBD369B8CA4FD6D5E59F07F" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_RatioofDebttoEBITDAtoIncreaseRevolvingCommitment_0A652664CEBD369B8CA4FD6D5E59F07F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_86F42BE304D27E420BE2FD6D5E59AC69" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_86F42BE304D27E420BE2FD6D5E59AC69" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityCollateralPercentofAssets" xlink:label="loc_tree_LineofCreditFacilityCollateralPercentofAssets_DE1381BF3AF5AB254B46FD6D5E598A40" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityCollateralPercentofAssets_DE1381BF3AF5AB254B46FD6D5E598A40" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityCollateralPercentofEquity" xlink:label="loc_tree_LineofCreditFacilityCollateralPercentofEquity_C45F0A091036366FB4F8FD6D5E59CD4A" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityCollateralPercentofEquity_C45F0A091036366FB4F8FD6D5E59CD4A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_81C05F79DA2311DCA972FD6D5E5937B6" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_81C05F79DA2311DCA972FD6D5E5937B6" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityLetterofCreditParticipationFeePercentage" xlink:label="loc_tree_LineofCreditFacilityLetterofCreditParticipationFeePercentage_DF83CD6947FBDB6657F3FD6D5E59D216" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityLetterofCreditParticipationFeePercentage_DF83CD6947FBDB6657F3FD6D5E59D216" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityLetterofCreditFrontingFeePercentage" xlink:label="loc_tree_LineofCreditFacilityLetterofCreditFrontingFeePercentage_6F8FA8448660F1989328FD6D5E5987A2" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityLetterofCreditFrontingFeePercentage_6F8FA8448660F1989328FD6D5E5987A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentFeeAmount" xlink:label="loc_us-gaap_DebtInstrumentFeeAmount_6D7AA97C1291E2792E4BFD6D5E59A250" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_us-gaap_DebtInstrumentFeeAmount_6D7AA97C1291E2792E4BFD6D5E59A250" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_RatioofDebttoEBITDA" xlink:label="loc_tree_RatioofDebttoEBITDA_76854DFBA45F65F0E30DFD6D5E59F1A7" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_RatioofDebttoEBITDA_76854DFBA45F65F0E30DFD6D5E59F1A7" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_RatioofDebttoEBITDAStepDown" xlink:label="loc_tree_RatioofDebttoEBITDAStepDown_E39BACB43F857F60B24DFD6D5E597CC0" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_RatioofDebttoEBITDAStepDown_E39BACB43F857F60B24DFD6D5E597CC0" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_RatioofDebttoEBITDAIncrease" xlink:label="loc_tree_RatioofDebttoEBITDAIncrease_458C4EB13AF3FD2571C3FD6D5E5930D2" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_RatioofDebttoEBITDAIncrease_458C4EB13AF3FD2571C3FD6D5E5930D2" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityCollateralPercentofDomesticSubsidiariesEquity" xlink:label="loc_tree_LineofCreditFacilityCollateralPercentofDomesticSubsidiariesEquity_9BC317A4DEF0B6CF13CAFD6D5E5984EE" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityCollateralPercentofDomesticSubsidiariesEquity_9BC317A4DEF0B6CF13CAFD6D5E5984EE" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityCollateralPercentofVotingEquity" xlink:label="loc_tree_LineofCreditFacilityCollateralPercentofVotingEquity_0084E0154350CE9260D8FD6D5E59163F" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityCollateralPercentofVotingEquity_0084E0154350CE9260D8FD6D5E59163F" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LineofCreditFacilityCollateralPercentofNonVotingEquity" xlink:label="loc_tree_LineofCreditFacilityCollateralPercentofNonVotingEquity_2CE5BFCF8195A4110D9DFD6D5E5AF6B4" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_916F0FD0BE2056E96565FD6D5E59F598" xlink:to="loc_tree_LineofCreditFacilityCollateralPercentofNonVotingEquity_2CE5BFCF8195A4110D9DFD6D5E5AF6B4" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/DebtNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/DebtTable" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/DiscontinuedOperationsDetailsDisposalGroups" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_E2C01AF55FD05452839F0FB604780873" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_E2C01AF55FD05452839F0FB604780873" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_1B4DF2173CC354B1921B8197A1D5D1A9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_E2C01AF55FD05452839F0FB604780873" xlink:to="loc_us-gaap_StatementScenarioAxis_1B4DF2173CC354B1921B8197A1D5D1A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_728D779F2DE530B6FA6939408E4A16A1_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_1B4DF2173CC354B1921B8197A1D5D1A9" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_728D779F2DE530B6FA6939408E4A16A1_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_00B816A5A1B2575AA564E1822A922BCE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_1B4DF2173CC354B1921B8197A1D5D1A9" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_00B816A5A1B2575AA564E1822A922BCE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_0F82C3C9EF75535EBE59996FC2E4D958" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_E2C01AF55FD05452839F0FB604780873" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_0F82C3C9EF75535EBE59996FC2E4D958" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_110B042831D08FDA58D439408E4AC75A_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_0F82C3C9EF75535EBE59996FC2E4D958" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_110B042831D08FDA58D439408E4AC75A_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_DC497182AB26595CB117469941342B1E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_0F82C3C9EF75535EBE59996FC2E4D958" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_DC497182AB26595CB117469941342B1E" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LendingTreeLoansMember" xlink:label="loc_tree_LendingTreeLoansMember_005E4FEB14B2594BA4D17A43E7F16F2F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_DC497182AB26595CB117469941342B1E" xlink:to="loc_tree_LendingTreeLoansMember_005E4FEB14B2594BA4D17A43E7F16F2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CounterpartyNameAxis" xlink:label="loc_us-gaap_CounterpartyNameAxis_336E844C6D2256E3880E66DF5382A7CF" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_E2C01AF55FD05452839F0FB604780873" xlink:to="loc_us-gaap_CounterpartyNameAxis_336E844C6D2256E3880E66DF5382A7CF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_2EDFBD00C70529CBB4D139408E4B5013_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CounterpartyNameAxis_336E844C6D2256E3880E66DF5382A7CF" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_2EDFBD00C70529CBB4D139408E4B5013_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_19F904C6AC9657AAA920E89C2F3DED66" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CounterpartyNameAxis_336E844C6D2256E3880E66DF5382A7CF" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_19F904C6AC9657AAA920E89C2F3DED66" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_DiscoverBankMember" xlink:label="loc_tree_DiscoverBankMember_C8E1DDE2946455C9812FD246B72F74BB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_19F904C6AC9657AAA920E89C2F3DED66" xlink:to="loc_tree_DiscoverBankMember_C8E1DDE2946455C9812FD246B72F74BB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_8E68E315DD9B5D8583355F5238822DCD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_8E68E315DD9B5D8583355F5238822DCD" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_AssetPurchaseAgreementProceedsFromSale" xlink:label="loc_tree_AssetPurchaseAgreementProceedsFromSale_F55A3ED2A1F05D07B357D6D824F072F4" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:to="loc_tree_AssetPurchaseAgreementProceedsFromSale_F55A3ED2A1F05D07B357D6D824F072F4" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingencySettlementValue" xlink:label="loc_tree_LossContingencySettlementValue_7CC6E7DEEF2758EEB254C2E8302A7601" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:to="loc_tree_LossContingencySettlementValue_7CC6E7DEEF2758EEB254C2E8302A7601" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract_AECD127FC83E5755AEC65B156FEE3608" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract_AECD127FC83E5755AEC65B156FEE3608" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_13598781DA47579D84004179D8D7FC9A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract_AECD127FC83E5755AEC65B156FEE3608" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_13598781DA47579D84004179D8D7FC9A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax" xlink:label="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_7C044C5A19455D53BEFF47CB3AC79191" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract_AECD127FC83E5755AEC65B156FEE3608" xlink:to="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_7C044C5A19455D53BEFF47CB3AC79191" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation" xlink:label="loc_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_E7678939267E5E83BF54B4F418330C2D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract_AECD127FC83E5755AEC65B156FEE3608" xlink:to="loc_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_E7678939267E5E83BF54B4F418330C2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_0A3DF2892E835BAB82D3EAD4A020A711" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupNotDiscontinuedOperationIncomeStatementDisclosuresAbstract_AECD127FC83E5755AEC65B156FEE3608" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_0A3DF2892E835BAB82D3EAD4A020A711" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationBalanceSheetDisclosuresAbstract" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationBalanceSheetDisclosuresAbstract_1B3263C68CC45B3A927D67C718E0B0CD" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_FC5AB0481FB15904AE28CB3CC8849C64" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationBalanceSheetDisclosuresAbstract_1B3263C68CC45B3A927D67C718E0B0CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent_5F431C2421E853148C7CED0C3303A6C6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationBalanceSheetDisclosuresAbstract_1B3263C68CC45B3A927D67C718E0B0CD" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent_5F431C2421E853148C7CED0C3303A6C6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_6191232FD909500D9E1FC01FFDCE12A8" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationBalanceSheetDisclosuresAbstract_1B3263C68CC45B3A927D67C718E0B0CD" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperationCurrent_6191232FD909500D9E1FC01FFDCE12A8" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/DiscontinuedOperationsDetailsLoanLossObligations" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingenciesLineItems" xlink:label="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingenciesTable" xlink:label="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_CC7C558391D43A085F49FD6D5DEAF97F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:to="loc_us-gaap_RangeAxis_CC7C558391D43A085F49FD6D5DEAF97F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_273B3A2FE9620901B140FD6D5DEB2DAA_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_CC7C558391D43A085F49FD6D5DEAF97F" xlink:to="loc_us-gaap_RangeMember_273B3A2FE9620901B140FD6D5DEB2DAA_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_273B3A2FE9620901B140FD6D5DEB2DAA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_CC7C558391D43A085F49FD6D5DEAF97F" xlink:to="loc_us-gaap_RangeMember_273B3A2FE9620901B140FD6D5DEB2DAA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_0D788178FCBD9F087EBDFD6D5DEB3CFD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_273B3A2FE9620901B140FD6D5DEB2DAA" xlink:to="loc_us-gaap_MinimumMember_0D788178FCBD9F087EBDFD6D5DEB3CFD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_DAD7DB803F37E5F7F018FD6D5DEB5098" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_273B3A2FE9620901B140FD6D5DEB2DAA" xlink:to="loc_us-gaap_MaximumMember_DAD7DB803F37E5F7F018FD6D5DEB5098" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_InvestorAxis" xlink:label="loc_tree_InvestorAxis_FFB2C865BA231B7CABFEFD6D5DEB7DE6" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:to="loc_tree_InvestorAxis_FFB2C865BA231B7CABFEFD6D5DEB7DE6" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_InvestorDomain" xlink:label="loc_tree_InvestorDomain_A9B11652FA72BC1D3187FD6D5DEB6710_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_tree_InvestorAxis_FFB2C865BA231B7CABFEFD6D5DEB7DE6" xlink:to="loc_tree_InvestorDomain_A9B11652FA72BC1D3187FD6D5DEB6710_default" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_InvestorDomain" xlink:label="loc_tree_InvestorDomain_A9B11652FA72BC1D3187FD6D5DEB6710" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_tree_InvestorAxis_FFB2C865BA231B7CABFEFD6D5DEB7DE6" xlink:to="loc_tree_InvestorDomain_A9B11652FA72BC1D3187FD6D5DEB6710" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_InvestorOneMember" xlink:label="loc_tree_InvestorOneMember_DD47FA5D89CC60265A54FD6D5DEC6A18" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_InvestorDomain_A9B11652FA72BC1D3187FD6D5DEB6710" xlink:to="loc_tree_InvestorOneMember_DD47FA5D89CC60265A54FD6D5DEC6A18" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_InvestorTwoMember" xlink:label="loc_tree_InvestorTwoMember_9CF075E96BE41ED8800BFD6D5DED8F80" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_InvestorDomain_A9B11652FA72BC1D3187FD6D5DEB6710" xlink:to="loc_tree_InvestorTwoMember_9CF075E96BE41ED8800BFD6D5DED8F80" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CounterpartyNameAxis" xlink:label="loc_us-gaap_CounterpartyNameAxis_6693358FC35AAEFD4A63FD6D5DF27D02" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:to="loc_us-gaap_CounterpartyNameAxis_6693358FC35AAEFD4A63FD6D5DF27D02" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_F3C6F3F12BBFCD302775FD6D5DF28DC4_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CounterpartyNameAxis_6693358FC35AAEFD4A63FD6D5DF27D02" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_F3C6F3F12BBFCD302775FD6D5DF28DC4_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_F3C6F3F12BBFCD302775FD6D5DF28DC4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CounterpartyNameAxis_6693358FC35AAEFD4A63FD6D5DF27D02" xlink:to="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_F3C6F3F12BBFCD302775FD6D5DF28DC4" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_DiscoverBankMember" xlink:label="loc_tree_DiscoverBankMember_AD71DB5538EF9B3F736CFD6D5DF4FE21" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RepurchaseAgreementCounterpartyNameDomain_F3C6F3F12BBFCD302775FD6D5DF28DC4" xlink:to="loc_tree_DiscoverBankMember_AD71DB5538EF9B3F736CFD6D5DF4FE21" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_4B898A6CAEC49EC09A15FD6D5DF5C529" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_4B898A6CAEC49EC09A15FD6D5DF5C529" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_B553904C8182F863F20AFD6D5DF54A7E_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_4B898A6CAEC49EC09A15FD6D5DF5C529" xlink:to="loc_us-gaap_LossContingencyNatureDomain_B553904C8182F863F20AFD6D5DF54A7E_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_B553904C8182F863F20AFD6D5DF54A7E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_4B898A6CAEC49EC09A15FD6D5DF5C529" xlink:to="loc_us-gaap_LossContingencyNatureDomain_B553904C8182F863F20AFD6D5DF54A7E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ObligationToRepurchaseReceivablesSoldMember" xlink:label="loc_us-gaap_ObligationToRepurchaseReceivablesSoldMember_76D42692CA89BC1A3778FD6D5DF579AF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_B553904C8182F863F20AFD6D5DF54A7E" xlink:to="loc_us-gaap_ObligationToRepurchaseReceivablesSoldMember_76D42692CA89BC1A3778FD6D5DF579AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F2C39EE30DABE635892BFD6D5DF6BB78" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F2C39EE30DABE635892BFD6D5DF6BB78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_B48E143002FCFC3181CBFD6D5DF65B67_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F2C39EE30DABE635892BFD6D5DF6BB78" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_B48E143002FCFC3181CBFD6D5DF65B67_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_B48E143002FCFC3181CBFD6D5DF65B67" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F2C39EE30DABE635892BFD6D5DF6BB78" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_B48E143002FCFC3181CBFD6D5DF65B67" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LendingTreeLoansMember" xlink:label="loc_tree_LendingTreeLoansMember_48B42F9F30EAF39F5693FD6D5DF6F29E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_B48E143002FCFC3181CBFD6D5DF65B67" xlink:to="loc_tree_LendingTreeLoansMember_48B42F9F30EAF39F5693FD6D5DF6F29E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOperatingActivitiesSegmentAxis" xlink:label="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_76DDF75C1B22FEA399B0FD6D5DF61184" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_264F0E3DACF131897433FD6D5DEA5F06" xlink:to="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_76DDF75C1B22FEA399B0FD6D5DF61184" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentOperatingActivitiesDomain" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_A9DACC7DCF1A6AF70DDAFD6D5DF672E7_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_76DDF75C1B22FEA399B0FD6D5DF61184" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_A9DACC7DCF1A6AF70DDAFD6D5DF672E7_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentOperatingActivitiesDomain" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_A9DACC7DCF1A6AF70DDAFD6D5DF672E7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_76DDF75C1B22FEA399B0FD6D5DF61184" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_A9DACC7DCF1A6AF70DDAFD6D5DF672E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDiscontinuedOperationsMember" xlink:label="loc_us-gaap_SegmentDiscontinuedOperationsMember_F7576DDF135EADA23AF7FD6D5DF79126" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentOperatingActivitiesDomain_A9DACC7DCF1A6AF70DDAFD6D5DF672E7" xlink:to="loc_us-gaap_SegmentDiscontinuedOperationsMember_F7576DDF135EADA23AF7FD6D5DF79126" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_0B0823EA04E138A7EDF6FD6D5DF7F9AC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue_0B0823EA04E138A7EDF6FD6D5DF7F9AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_704DC89569E866687B26FD6D5DF7C41A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_704DC89569E866687B26FD6D5DF7C41A" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesNumberofLoansSold" xlink:label="loc_tree_LossContingenciesNumberofLoansSold_BD61E12E1627D4470858FD6D5DF7B45E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesNumberofLoansSold_BD61E12E1627D4470858FD6D5DF7B45E" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesOriginalPrincipalBalance" xlink:label="loc_tree_LossContingenciesOriginalPrincipalBalance_9AEB0E6AD46D8CCA02B7FD6D5DF72388" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesOriginalPrincipalBalance_9AEB0E6AD46D8CCA02B7FD6D5DF72388" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesNumberofLoansSubsequentlySettled" xlink:label="loc_tree_LossContingenciesNumberofLoansSubsequentlySettled_051EBC381F8DC311DE51FD6D5DF7B905" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesNumberofLoansSubsequentlySettled_051EBC381F8DC311DE51FD6D5DF7B905" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesValueofLoansSubsequentlySettled" xlink:label="loc_tree_LossContingenciesValueofLoansSubsequentlySettled_4F5E7226B8F878DA365AFD6D5DF7484E" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesValueofLoansSubsequentlySettled_4F5E7226B8F878DA365AFD6D5DF7484E" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesNumberofUnsettledLoansRemaining" xlink:label="loc_tree_LossContingenciesNumberofUnsettledLoansRemaining_232D11DE56BEF84E73D5FD6D5DF738C0" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesNumberofUnsettledLoansRemaining_232D11DE56BEF84E73D5FD6D5DF738C0" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesRemainingUnsettledLoans" xlink:label="loc_tree_LossContingenciesRemainingUnsettledLoans_B508472CF0344E11A922FD6D5DF88BEB" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesRemainingUnsettledLoans_B508472CF0344E11A922FD6D5DF88BEB" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingencySettlementValue" xlink:label="loc_tree_LossContingencySettlementValue_D739D7A14A426FB72A00FD6D5DF8E201" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingencySettlementValue_D739D7A14A426FB72A00FD6D5DF8E201" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesNumberofLoansSoldtooneinvestor" xlink:label="loc_tree_LossContingenciesNumberofLoansSoldtooneinvestor_AA243C2D86D7D06B26BBFD6D5DF83296" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesNumberofLoansSoldtooneinvestor_AA243C2D86D7D06B26BBFD6D5DF83296" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesPercentageoftheOriginalLoanIssueBalance" xlink:label="loc_tree_LossContingenciesPercentageoftheOriginalLoanIssueBalance_83BFF7970C308412099DFD6D5DF8BE6D" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesPercentageoftheOriginalLoanIssueBalance_83BFF7970C308412099DFD6D5DF8BE6D" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingenciesSettlementNumberOfBuyersOfPreviouslyPurchasedLimitedDocumentationLoans" xlink:label="loc_tree_LossContingenciesSettlementNumberOfBuyersOfPreviouslyPurchasedLimitedDocumentationLoans_943E87B33495308FC05DFD6D5DF8F2FB" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_LossContingenciesSettlementNumberOfBuyersOfPreviouslyPurchasedLimitedDocumentationLoans_943E87B33495308FC05DFD6D5DF8F2FB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyEstimateOfPossibleLoss" xlink:label="loc_us-gaap_LossContingencyEstimateOfPossibleLoss_3D41E4E16DE5D3E307ACFD6D5DF8A295" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_us-gaap_LossContingencyEstimateOfPossibleLoss_3D41E4E16DE5D3E307ACFD6D5DF8A295" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyAccrualAtCarryingValue" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_A25F56BAE843D10E3BC2FD6D5DF8E734" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_us-gaap_LossContingencyAccrualAtCarryingValue_A25F56BAE843D10E3BC2FD6D5DF8E734" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_GuaranteeObligationsNumberOfInvestorsToWhomLoansGuaranteed" xlink:label="loc_tree_GuaranteeObligationsNumberOfInvestorsToWhomLoansGuaranteed_191F83183E89E83412DCFD6D5DF9C79A" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_tree_GuaranteeObligationsNumberOfInvestorsToWhomLoansGuaranteed_191F83183E89E83412DCFD6D5DF9C79A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyAccrualRollForward" xlink:label="loc_us-gaap_LossContingencyAccrualRollForward_DE15A4B161010DD44E29FD6D5DF950F5" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_5220B60EC081E737E2CFFD6D5DF7647A" xlink:to="loc_us-gaap_LossContingencyAccrualRollForward_DE15A4B161010DD44E29FD6D5DF950F5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LossContingencyAccrualProvision" xlink:label="loc_us-gaap_LossContingencyAccrualProvision_8C2CE0966D285FA13FC1FD6D5DFE7C18" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyAccrualRollForward_DE15A4B161010DD44E29FD6D5DF950F5" xlink:to="loc_us-gaap_LossContingencyAccrualProvision_8C2CE0966D285FA13FC1FD6D5DFE7C18" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LossContingencyAccrualCarryingValueChargeOffs" xlink:label="loc_tree_LossContingencyAccrualCarryingValueChargeOffs_B400ED646851A1CA5570FD6D5DFFC33C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyAccrualRollForward_DE15A4B161010DD44E29FD6D5DF950F5" xlink:to="loc_tree_LossContingencyAccrualCarryingValueChargeOffs_B400ED646851A1CA5570FD6D5DFFC33C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/DiscontinuedOperationsNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/DiscontinuedOperationsTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_440389F05D145D9788366175D4ABC727" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_01F9171BDC11550DA68664699460F263" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_440389F05D145D9788366175D4ABC727" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_01F9171BDC11550DA68664699460F263" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_3B8055C95BE25AF59A3469A4F8EE4C73" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_01F9171BDC11550DA68664699460F263" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_3B8055C95BE25AF59A3469A4F8EE4C73" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_FCC3133F3AABEBB031E839408E67FB2D_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_3B8055C95BE25AF59A3469A4F8EE4C73" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_FCC3133F3AABEBB031E839408E67FB2D_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_EB60E30F926B59EFB3587B22272653AB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_3B8055C95BE25AF59A3469A4F8EE4C73" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_EB60E30F926B59EFB3587B22272653AB" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_LendingTreeLoansMember" xlink:label="loc_tree_LendingTreeLoansMember_149E2AE1EB2C50CA8354E96FC0B086ED" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_EB60E30F926B59EFB3587B22272653AB" xlink:to="loc_tree_LendingTreeLoansMember_149E2AE1EB2C50CA8354E96FC0B086ED" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementTableTextBlock" xlink:label="loc_tree_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementTableTextBlock_D75C56F74A9B5966BF8976B75E26FC2F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_440389F05D145D9788366175D4ABC727" xlink:to="loc_tree_ScheduleOfDisposalGroupsIncludingDiscontinuedOperationsIncomeStatementTableTextBlock_D75C56F74A9B5966BF8976B75E26FC2F" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ScheduleoftheNumberandIssueBalanceofLoansSoldandSubsequentSettlementsTableTextBlock" xlink:label="loc_tree_ScheduleoftheNumberandIssueBalanceofLoansSoldandSubsequentSettlementsTableTextBlock_117EA4FA3E8751ED96EA3BEE391922D4" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_440389F05D145D9788366175D4ABC727" xlink:to="loc_tree_ScheduleoftheNumberandIssueBalanceofLoansSoldandSubsequentSettlementsTableTextBlock_117EA4FA3E8751ED96EA3BEE391922D4" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ScheduleOfActivityInLossReservesOnLoansSoldTableTextBlock" xlink:label="loc_tree_ScheduleOfActivityInLossReservesOnLoansSoldTableTextBlock_C6F998566FEE5563BC145BA75AFB7FC2" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_440389F05D145D9788366175D4ABC727" xlink:to="loc_tree_ScheduleOfActivityInLossReservesOnLoansSoldTableTextBlock_C6F998566FEE5563BC145BA75AFB7FC2" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/DocumentAndEntityInformation" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityInformationLineItems" xlink:label="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntitiesTable" xlink:label="loc_dei_EntitiesTable_A50A755FF4C65D15A9D2971A4F1405FA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_EntitiesTable_A50A755FF4C65D15A9D2971A4F1405FA" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_LegalEntityAxis" xlink:label="loc_dei_LegalEntityAxis_B3C240AA0B155BDF8E032EBBFE157CA8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_EntitiesTable_A50A755FF4C65D15A9D2971A4F1405FA" xlink:to="loc_dei_LegalEntityAxis_B3C240AA0B155BDF8E032EBBFE157CA8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_A563FE16205D6B42CFAD39408F666495_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_B3C240AA0B155BDF8E032EBBFE157CA8" xlink:to="loc_dei_EntityDomain_A563FE16205D6B42CFAD39408F666495_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_5103C8C4ECA055ABA3F51ED93118B76F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_B3C240AA0B155BDF8E032EBBFE157CA8" xlink:to="loc_dei_EntityDomain_5103C8C4ECA055ABA3F51ED93118B76F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_42CB3423A57D5F6688D63BD0BC57039C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_EntityRegistrantName_42CB3423A57D5F6688D63BD0BC57039C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_5C6AB8BB2D0451DF8F5EE892F623AC00" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_EntityCentralIndexKey_5C6AB8BB2D0451DF8F5EE892F623AC00" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_49F7519785E95794AF41636A65D9DC84" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_DocumentType_49F7519785E95794AF41636A65D9DC84" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_221036FF0BE755609A15E729D68F5650" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_DocumentPeriodEndDate_221036FF0BE755609A15E729D68F5650" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_D48A0002EFB2594B8AD3F2A0CACF0C1C" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_AmendmentFlag_D48A0002EFB2594B8AD3F2A0CACF0C1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_dei_CurrentFiscalYearEndDate_3C336BB20AF6572EAD91C4411199E4F2" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_CurrentFiscalYearEndDate_3C336BB20AF6572EAD91C4411199E4F2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCurrentReportingStatus" xlink:label="loc_dei_EntityCurrentReportingStatus_FA3C657A40515EFFAC4E4E569EDF4671" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_EntityCurrentReportingStatus_FA3C657A40515EFFAC4E4E569EDF4671" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory_623383346108599BB184625250998ACA" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_EntityFilerCategory_623383346108599BB184625250998ACA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_344E972B71C7502AA3ACC7D9D8C04E97" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_344E972B71C7502AA3ACC7D9D8C04E97" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_dei_DocumentFiscalYearFocus_6410E3FD11695916A9A733CA704EECA7" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_DocumentFiscalYearFocus_6410E3FD11695916A9A733CA704EECA7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_dei_DocumentFiscalPeriodFocus_61B822ADAA9C560C848C276A6D69B70E" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityInformationLineItems_526F636F45985AACB2165A593724319C" xlink:to="loc_dei_DocumentFiscalPeriodFocus_61B822ADAA9C560C848C276A6D69B70E" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/FairValueMeasurementsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_DF930D8F15DFC5007A48FD6D5E34EFD1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_802251D354A833CCE79DFD6D5E2EEF6E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_DF930D8F15DFC5007A48FD6D5E34EFD1" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_802251D354A833CCE79DFD6D5E2EEF6E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_B4566C834EFF00867D29FD6D5E2E7223" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_802251D354A833CCE79DFD6D5E2EEF6E" xlink:to="loc_us-gaap_RangeAxis_B4566C834EFF00867D29FD6D5E2E7223" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_3C4AE1D8B3D103CFB9AAFD6D5E321C91_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_B4566C834EFF00867D29FD6D5E2E7223" xlink:to="loc_us-gaap_RangeMember_3C4AE1D8B3D103CFB9AAFD6D5E321C91_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_3C4AE1D8B3D103CFB9AAFD6D5E321C91" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_B4566C834EFF00867D29FD6D5E2E7223" xlink:to="loc_us-gaap_RangeMember_3C4AE1D8B3D103CFB9AAFD6D5E321C91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_80F7A7C0BE470F9DB0CFFD6D5E32A28C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_3C4AE1D8B3D103CFB9AAFD6D5E321C91" xlink:to="loc_us-gaap_MinimumMember_80F7A7C0BE470F9DB0CFFD6D5E32A28C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_6DC6CD5E778209414C3BFD6D5E321434" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_3C4AE1D8B3D103CFB9AAFD6D5E321C91" xlink:to="loc_us-gaap_MaximumMember_6DC6CD5E778209414C3BFD6D5E321434" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_72CCA3074A9CBD6EFD49FD6D5E345F26" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_DF930D8F15DFC5007A48FD6D5E34EFD1" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_72CCA3074A9CBD6EFD49FD6D5E345F26" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_484CFFF3FC1A6D1878F1FD6D5E341DE3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_DF930D8F15DFC5007A48FD6D5E34EFD1" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiability_484CFFF3FC1A6D1878F1FD6D5E341DE3" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/FairValueMeasurementsNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/FairValueMeasurementsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/GoodwillAndIntangibleAssetsDetails5YrDefiniteLivedIntangiblesAmortization" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/GoodwillAndIntangibleAssetsDetailsBalanceSheet" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/GoodwillAndIntangibleAssetsDetailsDefiniteLivedIntangibles" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_FD99AC1E0AE11C39400EDEEBB9E0B498" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_1CC919FAEA1D6654F468DEEBB9DFF660" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_FD99AC1E0AE11C39400EDEEBB9E0B498" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_1CC919FAEA1D6654F468DEEBB9DFF660" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_FF4AA5AE16077914F9CBDEEBB9DF0D5C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_1CC919FAEA1D6654F468DEEBB9DFF660" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_FF4AA5AE16077914F9CBDEEBB9DF0D5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_FF4AA5AE16077914F9CBDEEBB9DF0D5C" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_FF4AA5AE16077914F9CBDEEBB9DF0D5C" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_490A53DABCE7E8EBFA2EDEEBB9DF6F1C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_490A53DABCE7E8EBFA2EDEEBB9DF6F1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerListsMember" xlink:label="loc_us-gaap_CustomerListsMember_3DDF3BE0F3FE7AFFD630DEEBB9DF446C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:to="loc_us-gaap_CustomerListsMember_3DDF3BE0F3FE7AFFD630DEEBB9DF446C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TrademarksAndTradeNamesMember" xlink:label="loc_us-gaap_TrademarksAndTradeNamesMember_B24DBB2694582D0A9A3FDEEBB9DF0634" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:to="loc_us-gaap_TrademarksAndTradeNamesMember_B24DBB2694582D0A9A3FDEEBB9DF0634" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LeasesAcquiredInPlaceMember" xlink:label="loc_us-gaap_LeasesAcquiredInPlaceMember_28A3C37159438275ECA7DEEBB9DF4BF1" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:to="loc_us-gaap_LeasesAcquiredInPlaceMember_28A3C37159438275ECA7DEEBB9DF4BF1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MediaContentMember" xlink:label="loc_us-gaap_MediaContentMember_E9446C4C512CEF006EFFDEEBB9DFAF24" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:to="loc_us-gaap_MediaContentMember_E9446C4C512CEF006EFFDEEBB9DFAF24" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherIntangibleAssetsMember" xlink:label="loc_us-gaap_OtherIntangibleAssetsMember_4E744B72B321EF3193E4DEEBB9E05043" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_58CB86FD198FBC519207DEEBB9DF3D94" xlink:to="loc_us-gaap_OtherIntangibleAssetsMember_4E744B72B321EF3193E4DEEBB9E05043" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_4CE71B8B59CC752B6811DEEBB9E06E8E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_FD99AC1E0AE11C39400EDEEBB9E0B498" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_4CE71B8B59CC752B6811DEEBB9E06E8E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_EC871576480A9D0517A0DEEBB9E0188C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_FD99AC1E0AE11C39400EDEEBB9E0B498" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_EC871576480A9D0517A0DEEBB9E0188C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_9F8A53A68FAF0AFA7E7EDEEBB9E0498B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_FD99AC1E0AE11C39400EDEEBB9E0B498" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_9F8A53A68FAF0AFA7E7EDEEBB9E0498B" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/GoodwillAndIntangibleAssetsGoodwillAndIntangibleAssetsDetailsNarrativeDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/GoodwillAndIntangibleAssetsNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/GoodwillAndIntangibleAssetsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/IncomeTaxesDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/IncomeTaxesNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/IncomeTaxesTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/OrganizationNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/RevenueDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_3EABB86DE6A1D343B78407A084B46817" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_3EABB86DE6A1D343B78407A084B46817" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_5759D6959057D62810BE07A084B38DF2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_5759D6959057D62810BE07A084B38DF2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_7157614A24EF0D9F06FE07A084B3E572_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_5759D6959057D62810BE07A084B38DF2" xlink:to="loc_us-gaap_SegmentDomain_7157614A24EF0D9F06FE07A084B3E572_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_7157614A24EF0D9F06FE07A084B3E572" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_5759D6959057D62810BE07A084B38DF2" xlink:to="loc_us-gaap_SegmentDomain_7157614A24EF0D9F06FE07A084B3E572" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="loc_us-gaap_ProductOrServiceAxis_395CB00105D61251787E07A084B334CD" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_ProductOrServiceAxis_395CB00105D61251787E07A084B334CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ProductOrServiceAxis_395CB00105D61251787E07A084B334CD" xlink:to="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ProductOrServiceAxis_395CB00105D61251787E07A084B334CD" xlink:to="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_MortgageProductsMember" xlink:label="loc_tree_MortgageProductsMember_45F8E5D2B095D0BC857707A084B49FA9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:to="loc_tree_MortgageProductsMember_45F8E5D2B095D0BC857707A084B49FA9" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_CreditCardsMember" xlink:label="loc_tree_CreditCardsMember_68C45954BEFF851A5A3007A084B4E08C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:to="loc_tree_CreditCardsMember_68C45954BEFF851A5A3007A084B4E08C" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_PersonalLoansMember" xlink:label="loc_tree_PersonalLoansMember_ACDEA5B40D727539875A07A084B46DEA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:to="loc_tree_PersonalLoansMember_ACDEA5B40D727539875A07A084B46DEA" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_OtherProductsAndServicesMember" xlink:label="loc_tree_OtherProductsAndServicesMember_6F6F983780C11BB3969E07A084B466A7" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:to="loc_tree_OtherProductsAndServicesMember_6F6F983780C11BB3969E07A084B466A7" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_NonmortgageProductsMember" xlink:label="loc_tree_NonmortgageProductsMember_0ECA509B856AF8758BAF07A09DD30050" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_6DA66D52977FE9BCEEC407A084B41500" xlink:to="loc_tree_NonmortgageProductsMember_0ECA509B856AF8758BAF07A09DD30050" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementGeographicalAxis" xlink:label="loc_us-gaap_StatementGeographicalAxis_CA8E4DC64318C1734EC007A084B44416" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_StatementGeographicalAxis_CA8E4DC64318C1734EC007A084B44416" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_E1DB70F2BB227198F0E707A084B47D98_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementGeographicalAxis_CA8E4DC64318C1734EC007A084B44416" xlink:to="loc_us-gaap_SegmentGeographicalDomain_E1DB70F2BB227198F0E707A084B47D98_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentGeographicalDomain" xlink:label="loc_us-gaap_SegmentGeographicalDomain_E1DB70F2BB227198F0E707A084B47D98" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementGeographicalAxis_CA8E4DC64318C1734EC007A084B44416" xlink:to="loc_us-gaap_SegmentGeographicalDomain_E1DB70F2BB227198F0E707A084B47D98" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingAxis" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_A676AD9B8C8BBEB5DCF307A084B4B878" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_A676AD9B8C8BBEB5DCF307A084B4B878" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_CF5081888729ECADE3F407A084B4D455_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_A676AD9B8C8BBEB5DCF307A084B4B878" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_CF5081888729ECADE3F407A084B4D455_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_CF5081888729ECADE3F407A084B4D455" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_A676AD9B8C8BBEB5DCF307A084B4B878" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_CF5081888729ECADE3F407A084B4D455" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerDurationAxis" xlink:label="loc_us-gaap_ContractWithCustomerDurationAxis_CAA7A5BF28E5CA844C6407A084B4460B" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_ContractWithCustomerDurationAxis_CAA7A5BF28E5CA844C6407A084B4460B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerDurationDomain" xlink:label="loc_us-gaap_ContractWithCustomerDurationDomain_44E7B0EA3654D3C182E907A084B4B44D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerDurationAxis_CAA7A5BF28E5CA844C6407A084B4460B" xlink:to="loc_us-gaap_ContractWithCustomerDurationDomain_44E7B0EA3654D3C182E907A084B4B44D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerDurationDomain" xlink:label="loc_us-gaap_ContractWithCustomerDurationDomain_44E7B0EA3654D3C182E907A084B4B44D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerDurationAxis_CAA7A5BF28E5CA844C6407A084B4460B" xlink:to="loc_us-gaap_ContractWithCustomerDurationDomain_44E7B0EA3654D3C182E907A084B4B44D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TimingOfTransferOfGoodOrServiceAxis" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_2D7EE0F31CBD4A30804E07A084B46D56" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_2D7EE0F31CBD4A30804E07A084B46D56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_99A370BB24E16B61DD9407A084B4F6F9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_2D7EE0F31CBD4A30804E07A084B46D56" xlink:to="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_99A370BB24E16B61DD9407A084B4F6F9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_99A370BB24E16B61DD9407A084B4F6F9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_2D7EE0F31CBD4A30804E07A084B46D56" xlink:to="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_99A370BB24E16B61DD9407A084B4F6F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerSalesChannelAxis" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelAxis_5AE4AC3F56DFD322D53907A084B40082" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelAxis_5AE4AC3F56DFD322D53907A084B40082" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerSalesChannelDomain" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelDomain_CBE0D2BA2195C82F272407A084B4AAF8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelAxis_5AE4AC3F56DFD322D53907A084B40082" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelDomain_CBE0D2BA2195C82F272407A084B4AAF8_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerSalesChannelDomain" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelDomain_CBE0D2BA2195C82F272407A084B4AAF8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelAxis_5AE4AC3F56DFD322D53907A084B40082" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelDomain_CBE0D2BA2195C82F272407A084B4AAF8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorCustomersAxis" xlink:label="loc_us-gaap_MajorCustomersAxis_31BFD5C269D699B42B9707A084B4744A" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_A45F7409A196162008A007A084B3449E" xlink:to="loc_us-gaap_MajorCustomersAxis_31BFD5C269D699B42B9707A084B4744A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="loc_us-gaap_NameOfMajorCustomerDomain_C6028146AE100B550CF107A084B44CF6_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorCustomersAxis_31BFD5C269D699B42B9707A084B4744A" xlink:to="loc_us-gaap_NameOfMajorCustomerDomain_C6028146AE100B550CF107A084B44CF6_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NameOfMajorCustomerDomain" xlink:label="loc_us-gaap_NameOfMajorCustomerDomain_C6028146AE100B550CF107A084B44CF6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorCustomersAxis_31BFD5C269D699B42B9707A084B4744A" xlink:to="loc_us-gaap_NameOfMajorCustomerDomain_C6028146AE100B550CF107A084B44CF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_9A8AF0B14538503CB56507A084B4AC77" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_3EABB86DE6A1D343B78407A084B46817" xlink:to="loc_us-gaap_Revenues_9A8AF0B14538503CB56507A084B4AC77" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/RevenueNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/RevenueScheduleOfRevenueTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/SegmentInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_805E3877D8BDBD4F1175FF67BA4EC36E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_7DEBE103B10F5187E28CFF67BA4E9993" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_805E3877D8BDBD4F1175FF67BA4EC36E" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_7DEBE103B10F5187E28CFF67BA4E9993" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="loc_us-gaap_ProductOrServiceAxis_999C4A2AFFE9F4A2681AFF67BA4E3FF1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_7DEBE103B10F5187E28CFF67BA4E9993" xlink:to="loc_us-gaap_ProductOrServiceAxis_999C4A2AFFE9F4A2681AFF67BA4E3FF1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_B15454CA6322745A017FFF67BA4ED3BF_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ProductOrServiceAxis_999C4A2AFFE9F4A2681AFF67BA4E3FF1" xlink:to="loc_us-gaap_ProductsAndServicesDomain_B15454CA6322745A017FFF67BA4ED3BF_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_B15454CA6322745A017FFF67BA4ED3BF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ProductOrServiceAxis_999C4A2AFFE9F4A2681AFF67BA4E3FF1" xlink:to="loc_us-gaap_ProductsAndServicesDomain_B15454CA6322745A017FFF67BA4ED3BF" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_MortgageProductsMember" xlink:label="loc_tree_MortgageProductsMember_697F1A5EA836AB7C3AB3FF67BA4EE311" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_B15454CA6322745A017FFF67BA4ED3BF" xlink:to="loc_tree_MortgageProductsMember_697F1A5EA836AB7C3AB3FF67BA4EE311" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_NonmortgageProductsMember" xlink:label="loc_tree_NonmortgageProductsMember_ED605348622CC80B213DFF67BA4E238C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ProductsAndServicesDomain_B15454CA6322745A017FFF67BA4ED3BF" xlink:to="loc_tree_NonmortgageProductsMember_ED605348622CC80B213DFF67BA4E238C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_6EF8611D52A0F291666FFF67BA4ECAB6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_805E3877D8BDBD4F1175FF67BA4EC36E" xlink:to="loc_us-gaap_Revenues_6EF8611D52A0F291666FFF67BA4ECAB6" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/SegmentInformationNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/SegmentInformationTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/ShareholdersEquityDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_4FA4C6136D20A3048479FF6F430F6F84" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_257409C6891C60E7EEC5FF6F430E993D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_4FA4C6136D20A3048479FF6F430F6F84" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_257409C6891C60E7EEC5FF6F430E993D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_152997F843711C353BF8FF6F430FAC64" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_257409C6891C60E7EEC5FF6F430E993D" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_152997F843711C353BF8FF6F430FAC64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A1795DCA603DB7C0CF6DFF6F430F96CA_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_152997F843711C353BF8FF6F430FAC64" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A1795DCA603DB7C0CF6DFF6F430F96CA_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A1795DCA603DB7C0CF6DFF6F430F96CA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_152997F843711C353BF8FF6F430FAC64" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A1795DCA603DB7C0CF6DFF6F430F96CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_1E2CA08C24F8945067CCFF6F430F703E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A1795DCA603DB7C0CF6DFF6F430F96CA" xlink:to="loc_us-gaap_EmployeeStockOptionMember_1E2CA08C24F8945067CCFF6F430F703E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_1C615F6BF084D6B71E58FF6F430F253C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_4FA4C6136D20A3048479FF6F430F6F84" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_1C615F6BF084D6B71E58FF6F430F253C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/ShareholdersEquityNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/ShareholdersEquityTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/SignificantAccountingPoliciesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_57179DAFB62D8167605DFF67BBAB8E55" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable" xlink:label="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_9B9A5B652CB39CBE0CF4FF67BBAA0F42" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_57179DAFB62D8167605DFF67BBAB8E55" xlink:to="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_9B9A5B652CB39CBE0CF4FF67BBAA0F42" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_A44903BC781451069BB3FF67BBAAC14D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_9B9A5B652CB39CBE0CF4FF67BBAA0F42" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_A44903BC781451069BB3FF67BBAAC14D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C846CB2CC578A353F66BFF67BBAA0FC9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_A44903BC781451069BB3FF67BBAAC14D" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C846CB2CC578A353F66BFF67BBAA0FC9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C846CB2CC578A353F66BFF67BBAA0FC9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_A44903BC781451069BB3FF67BBAAC14D" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C846CB2CC578A353F66BFF67BBAA0FC9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member" xlink:label="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_4CFC1C30E5274376A300FF67BBAA11C4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C846CB2CC578A353F66BFF67BBAA0FC9" xlink:to="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_4CFC1C30E5274376A300FF67BBAA11C4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member" xlink:label="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_EF920DB497302620A8ECFF67BBAA9A0C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C846CB2CC578A353F66BFF67BBAA0FC9" xlink:to="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_EF920DB497302620A8ECFF67BBAA9A0C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_C2C8424762DC2DBE00BFFF67BBAA4326" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionTable_9B9A5B652CB39CBE0CF4FF67BBAA0F42" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_C2C8424762DC2DBE00BFFF67BBAA4326" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_9E94880C2E060F4677EBFF67BBAA3D92_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_C2C8424762DC2DBE00BFFF67BBAA4326" xlink:to="loc_us-gaap_TypeOfAdoptionMember_9E94880C2E060F4677EBFF67BBAA3D92_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_9E94880C2E060F4677EBFF67BBAA3D92" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_C2C8424762DC2DBE00BFFF67BBAA4326" xlink:to="loc_us-gaap_TypeOfAdoptionMember_9E94880C2E060F4677EBFF67BBAA3D92" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_EC2B726BD904C566E4DEFF67BBAAA59D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_9E94880C2E060F4677EBFF67BBAA3D92" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_EC2B726BD904C566E4DEFF67BBAAA59D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BalanceSheetRelatedDisclosuresAbstract" xlink:label="loc_us-gaap_BalanceSheetRelatedDisclosuresAbstract_87462D2C50BA9E384C93FF67BBAB4D74" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_57179DAFB62D8167605DFF67BBAB8E55" xlink:to="loc_us-gaap_BalanceSheetRelatedDisclosuresAbstract_87462D2C50BA9E384C93FF67BBAB4D74" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_C05E249F5EB7F5245342FF67BBAB3DFD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetRelatedDisclosuresAbstract_87462D2C50BA9E384C93FF67BBAB4D74" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_C05E249F5EB7F5245342FF67BBAB3DFD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNetNoncurrent" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNetNoncurrent_8D82281E1F8D95C703E6FF67BBABBF4A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetRelatedDisclosuresAbstract_87462D2C50BA9E384C93FF67BBAB4D74" xlink:to="loc_us-gaap_DeferredTaxAssetsLiabilitiesNetNoncurrent_8D82281E1F8D95C703E6FF67BBABBF4A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_C3147C093003EC8EF0CBFF67BBABCC2C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetRelatedDisclosuresAbstract_87462D2C50BA9E384C93FF67BBAB4D74" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_C3147C093003EC8EF0CBFF67BBABCC2C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementRelatedDisclosuresAbstract" xlink:label="loc_us-gaap_IncomeStatementRelatedDisclosuresAbstract_B676B9753C9465C6C6DFFF67BBABE42F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueInitialApplicationPeriodCumulativeEffectTransitionLineItems_57179DAFB62D8167605DFF67BBAB8E55" xlink:to="loc_us-gaap_IncomeStatementRelatedDisclosuresAbstract_B676B9753C9465C6C6DFFF67BBABE42F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_6BF2243B5D6562EEB428FF67BBAB05DF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementRelatedDisclosuresAbstract_B676B9753C9465C6C6DFFF67BBABE42F" xlink:to="loc_us-gaap_Revenues_6BF2243B5D6562EEB428FF67BBAB05DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_AF0D32B0072D322A136AFF67BBAB1B06" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementRelatedDisclosuresAbstract_B676B9753C9465C6C6DFFF67BBABE42F" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_AF0D32B0072D322A136AFF67BBAB1B06" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeLossFromContinuingOperations" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_162C565D0A5FF2F40341FF67BBAB86AB" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementRelatedDisclosuresAbstract_B676B9753C9465C6C6DFFF67BBABE42F" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperations_162C565D0A5FF2F40341FF67BBAB86AB" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/SignificantAccountingPoliciesNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/SignificantAccountingPoliciesPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/SignificantAccountingPoliciesTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationDetailsChairmanAndChiefExecutiveOfficerGrants" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22761A38F8E056E8F28CFD6D5EDAE68E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22761A38F8E056E8F28CFD6D5EDAE68E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TitleOfIndividualAxis" xlink:label="loc_us-gaap_TitleOfIndividualAxis_C17ADE3845367D1C0A18FD9835A1BEAF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22761A38F8E056E8F28CFD6D5EDAE68E" xlink:to="loc_us-gaap_TitleOfIndividualAxis_C17ADE3845367D1C0A18FD9835A1BEAF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_AD207766AD1148D57916FD9835A53374_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TitleOfIndividualAxis_C17ADE3845367D1C0A18FD9835A1BEAF" xlink:to="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_AD207766AD1148D57916FD9835A53374_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_AD207766AD1148D57916FD9835A53374" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TitleOfIndividualAxis_C17ADE3845367D1C0A18FD9835A1BEAF" xlink:to="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_AD207766AD1148D57916FD9835A53374" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ChairmanAndChiefExecutiveOfficerMember" xlink:label="loc_tree_ChairmanAndChiefExecutiveOfficerMember_8BA348F8ED793ABFFC7DFD98F62DEF9D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_AD207766AD1148D57916FD9835A53374" xlink:to="loc_tree_ChairmanAndChiefExecutiveOfficerMember_8BA348F8ED793ABFFC7DFD98F62DEF9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_656C133000A1B0EE51FAFD6D5EDB8C5F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22761A38F8E056E8F28CFD6D5EDAE68E" xlink:to="loc_us-gaap_AwardTypeAxis_656C133000A1B0EE51FAFD6D5EDB8C5F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_656C133000A1B0EE51FAFD6D5EDB8C5F" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_656C133000A1B0EE51FAFD6D5EDB8C5F" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PerformanceSharesMember" xlink:label="loc_us-gaap_PerformanceSharesMember_34D15C49407DEB3BC665FD6D5EDCFD90" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562" xlink:to="loc_us-gaap_PerformanceSharesMember_34D15C49407DEB3BC665FD6D5EDCFD90" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_PerformanceOptionsMember" xlink:label="loc_tree_PerformanceOptionsMember_D257D613925F69112B2CFD6D5EDC815E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562" xlink:to="loc_tree_PerformanceOptionsMember_D257D613925F69112B2CFD6D5EDC815E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_642642DFEDD52D9BA90DFD6D5EDC519E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D86390652097EE1A9DBBFD6D5EDB8562" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_642642DFEDD52D9BA90DFD6D5EDC519E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_61E559C2414DD2ACE26DFD6D5EDCA9CC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22761A38F8E056E8F28CFD6D5EDAE68E" xlink:to="loc_us-gaap_RangeAxis_61E559C2414DD2ACE26DFD6D5EDCA9CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_C62AC17AAC98AE8A8223FD6D5EDCF91A_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_61E559C2414DD2ACE26DFD6D5EDCA9CC" xlink:to="loc_us-gaap_RangeMember_C62AC17AAC98AE8A8223FD6D5EDCF91A_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_C62AC17AAC98AE8A8223FD6D5EDCF91A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_61E559C2414DD2ACE26DFD6D5EDCA9CC" xlink:to="loc_us-gaap_RangeMember_C62AC17AAC98AE8A8223FD6D5EDCF91A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_EFDA0593BECA75F7B79EFD6D5EDDE7E7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_C62AC17AAC98AE8A8223FD6D5EDCF91A" xlink:to="loc_us-gaap_MaximumMember_EFDA0593BECA75F7B79EFD6D5EDDE7E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_984D05A89B2F059925EFFD6D5EDD11B2" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_C62AC17AAC98AE8A8223FD6D5EDCF91A" xlink:to="loc_us-gaap_MinimumMember_984D05A89B2F059925EFFD6D5EDD11B2" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_TargetGrantDateValueofPerformanceBasedEquityCompensation" xlink:label="loc_tree_TargetGrantDateValueofPerformanceBasedEquityCompensation_4AB54707C4F69D02298CFD6D5EDD9ACD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_TargetGrantDateValueofPerformanceBasedEquityCompensation_4AB54707C4F69D02298CFD6D5EDD9ACD" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_PercentageTargetGrantDateValueofPerformanceBasedEquityCompensationRestrictedStockAwards" xlink:label="loc_tree_PercentageTargetGrantDateValueofPerformanceBasedEquityCompensationRestrictedStockAwards_B4964ED55387F8819AFCFD6D5EDEA7E9" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_PercentageTargetGrantDateValueofPerformanceBasedEquityCompensationRestrictedStockAwards_B4964ED55387F8819AFCFD6D5EDEA7E9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_85B3EA56FE1C041D6C8BFD6D5EDEBC89" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_85B3EA56FE1C041D6C8BFD6D5EDEBC89" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_PercentageTargetGrantDateValueofPerformanceBasedEquityCompensationNonqualifiedStockOptions" xlink:label="loc_tree_PercentageTargetGrantDateValueofPerformanceBasedEquityCompensationNonqualifiedStockOptions_D3EAC56CB2879593FB45FD6D5EDEF570" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_PercentageTargetGrantDateValueofPerformanceBasedEquityCompensationNonqualifiedStockOptions_D3EAC56CB2879593FB45FD6D5EDEF570" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_MaximumPotentialFutureIssuanceofPerformanceStockOptions" xlink:label="loc_tree_MaximumPotentialFutureIssuanceofPerformanceStockOptions_B739376F627148CCC837FD6D5EDE4D21" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_MaximumPotentialFutureIssuanceofPerformanceStockOptions_B739376F627148CCC837FD6D5EDE4D21" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_TargetedTotalShareholderReturnPerformanceNonqualifiedStockOptions" xlink:label="loc_tree_TargetedTotalShareholderReturnPerformanceNonqualifiedStockOptions_4A1B81F1C4B48F0BDCA5FD6D5EDE6C63" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_TargetedTotalShareholderReturnPerformanceNonqualifiedStockOptions_4A1B81F1C4B48F0BDCA5FD6D5EDE6C63" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_A616A9E0C8CFC9321182FD89748C2896" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_A616A9E0C8CFC9321182FD89748C2896" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_77D44EB8538EFB69EEB1FD8A4E84E44E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_77D44EB8538EFB69EEB1FD8A4E84E44E" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_AnnaulGrantLimitPerEmployeeShares" xlink:label="loc_tree_AnnaulGrantLimitPerEmployeeShares_B1B816A8052305348135FD6D5EE4E736" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_AnnaulGrantLimitPerEmployeeShares_B1B816A8052305348135FD6D5EE4E736" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_C8BC116813660275508FFD6D5EDEFEDB" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_C8BC116813660275508FFD6D5EDEFEDB" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_PerformanceAwardsEarned" xlink:label="loc_tree_PerformanceAwardsEarned_E6FD41628480CA3FC254FD6D5EE5D72E" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_PerformanceAwardsEarned_E6FD41628480CA3FC254FD6D5EE5D72E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_A5409AFB6CCBA32FF6C6FD6D5EDE04B9" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_A5409AFB6CCBA32FF6C6FD6D5EDE04B9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_81DB471F6206CC67A902FD6D5EE445FB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_81DB471F6206CC67A902FD6D5EE445FB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_F97270B62B60D5F689A1FD6D5EE4A569" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_F97270B62B60D5F689A1FD6D5EE4A569" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_3CD16C15F86C515FEF2FFD6D5EE4F558" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_3CD16C15F86C515FEF2FFD6D5EE4F558" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_D487D07B3A49EC25DCB2FD6D5EE4E5AC" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_D487D07B3A49EC25DCB2FD6D5EE4E5AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_8175AAC91D582E596CC6FD6D5EE5B3A6" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_3C4C3D82648672E63982FD6D5EE46494" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_8175AAC91D582E596CC6FD6D5EE5B3A6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_FB7C7B2A26603DEFCE37FD6D5EE58592" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_FB7C7B2A26603DEFCE37FD6D5EE58592" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_2EC4C3F2CE168DA330CCFD6D5EE69BDD" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_2EC4C3F2CE168DA330CCFD6D5EE69BDD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_B99626D31DFC6BBDF230FD6D5EE8717B" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_B99626D31DFC6BBDF230FD6D5EE8717B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_31BCC98BA32DC5AB29DCFD6D5EE91C57" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_31BCC98BA32DC5AB29DCFD6D5EE91C57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_C20625F84DD72B84192CFD6D5EE91932" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_8002A63612A5EFAEABEBFD6D5EE544D9" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_C20625F84DD72B84192CFD6D5EE91932" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:label="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_4005445C17FDA0792D0BFD6D5EE97622" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_4005445C17FDA0792D0BFD6D5EE97622" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_1848F33FD81BC1233512FD6D5EE99137" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_4005445C17FDA0792D0BFD6D5EE97622" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_1848F33FD81BC1233512FD6D5EE99137" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_4C5619123AF3DFA4D058FD6D5EEA01CF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_4005445C17FDA0792D0BFD6D5EE97622" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_4C5619123AF3DFA4D058FD6D5EEA01CF" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:label="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_ABA7311B9F03185C2423FD6D5EEA8D99" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_ABA7311B9F03185C2423FD6D5EEA8D99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_753D6031AEE07EAF7FB5FD6D5EEB7FF4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_ABA7311B9F03185C2423FD6D5EEA8D99" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_753D6031AEE07EAF7FB5FD6D5EEB7FF4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_79B91EDD997809835D0CFD6D5EEB0844" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_ABA7311B9F03185C2423FD6D5EEA8D99" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_79B91EDD997809835D0CFD6D5EEB0844" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_8EE25D34B43A8471DD95FD6D5EDD0F75" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaap_SharePrice_150D0C648CB0E81F7C27FD6D5EECEFC4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_SharePrice_150D0C648CB0E81F7C27FD6D5EECEFC4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_F578A820BFDEBCFAB9C6FD6D5EEBE3AA" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_F578A820BFDEBCFAB9C6FD6D5EEBE3AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermSimplifiedMethod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermSimplifiedMethod_7D828264E22FBC799954FD6D5EEBE33B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermSimplifiedMethod_7D828264E22FBC799954FD6D5EEBE33B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_D7C3EAC6B6F6524B692AFD6D5EEBBD61" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_D7C3EAC6B6F6524B692AFD6D5EEBBD61" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_C0E0D9AEFD01FD686950FD74DE2A8C91" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_C0E0D9AEFD01FD686950FD74DE2A8C91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_121F11830353A889BFA5FD6D5EECA24D" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_121F11830353A889BFA5FD6D5EECA24D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_DEB924164230E7329978FD6D5EEC5838" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_DEB924164230E7329978FD6D5EEC5838" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_1290A47EA77F86F8FFBFFD6D5EEBB104" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_DA8A89ABF303781EDF83FD6D5EEBEF14" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_1290A47EA77F86F8FFBFFD6D5EEBB104" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationDetailsPlImpact" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_0E3496A8A5875D96B5A688D6A361A9F8" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_500DE18B70B65891B9F517613DC233FC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_0E3496A8A5875D96B5A688D6A361A9F8" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_500DE18B70B65891B9F517613DC233FC" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_B1CBC3F24FCB5207BEEBBBEAB8E60AAF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_500DE18B70B65891B9F517613DC233FC" xlink:to="loc_us-gaap_AwardTypeAxis_B1CBC3F24FCB5207BEEBBBEAB8E60AAF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_9EF344AC5BF42F04C0FE39408EB5B4FB_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_B1CBC3F24FCB5207BEEBBBEAB8E60AAF" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_9EF344AC5BF42F04C0FE39408EB5B4FB_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_272BBEF61429513ABE0DD9C107528F89" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_B1CBC3F24FCB5207BEEBBBEAB8E60AAF" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_272BBEF61429513ABE0DD9C107528F89" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_9C7AC9AF9F235ADAADCC174354326F37" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_500DE18B70B65891B9F517613DC233FC" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_9C7AC9AF9F235ADAADCC174354326F37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_5E21FFD62B1519BDB3F139408EB51F2D_CD55272B04765E2886727CF9E950FBD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_9C7AC9AF9F235ADAADCC174354326F37" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_5E21FFD62B1519BDB3F139408EB51F2D_CD55272B04765E2886727CF9E950FBD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_07A314346DBE5093A2B4049CA1F53FEB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_9C7AC9AF9F235ADAADCC174354326F37" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_07A314346DBE5093A2B4049CA1F53FEB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_FCEC8B1A63AC50A2B8B55AB7FEEA7B5A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_07A314346DBE5093A2B4049CA1F53FEB" xlink:to="loc_us-gaap_CostOfSalesMember_FCEC8B1A63AC50A2B8B55AB7FEEA7B5A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SellingAndMarketingExpenseMember" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_C3C07DA5F1AC50F3B806D0D0E4994563" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_07A314346DBE5093A2B4049CA1F53FEB" xlink:to="loc_us-gaap_SellingAndMarketingExpenseMember_C3C07DA5F1AC50F3B806D0D0E4994563" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_194E1699E6935FEAB5AE1E3404ACE3DA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_07A314346DBE5093A2B4049CA1F53FEB" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpenseMember_194E1699E6935FEAB5AE1E3404ACE3DA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_015B202B28095C8FA008EAFCEC484F59" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_07A314346DBE5093A2B4049CA1F53FEB" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseMember_015B202B28095C8FA008EAFCEC484F59" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_F5C8B6B14E8754F288E5048BEF9143FB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_0E3496A8A5875D96B5A688D6A361A9F8" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_F5C8B6B14E8754F288E5048BEF9143FB" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationDetailsRsaRsuRollforwards" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E8D7E69D01B7568DC4B9FD6D5F26CBFD" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_18C4CB65145654AD7149FD6D5F26C4A6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E8D7E69D01B7568DC4B9FD6D5F26CBFD" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_18C4CB65145654AD7149FD6D5F26C4A6" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_A4B8C45638060146D6ECFD6D5F26AD8C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_18C4CB65145654AD7149FD6D5F26C4A6" xlink:to="loc_us-gaap_AwardTypeAxis_A4B8C45638060146D6ECFD6D5F26AD8C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_A8CB39A99F379609D1DBFD6D5F263BE1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_A4B8C45638060146D6ECFD6D5F26AD8C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_A8CB39A99F379609D1DBFD6D5F263BE1_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_A8CB39A99F379609D1DBFD6D5F263BE1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_A4B8C45638060146D6ECFD6D5F26AD8C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_A8CB39A99F379609D1DBFD6D5F263BE1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_2BBB9E005A4577D9035CFD6D5F264E70" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_A8CB39A99F379609D1DBFD6D5F263BE1" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_2BBB9E005A4577D9035CFD6D5F264E70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_E5AD369E862BBC647E6FFD6D5F2739FA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E8D7E69D01B7568DC4B9FD6D5F26CBFD" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_E5AD369E862BBC647E6FFD6D5F2739FA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_67E50E890FE0F139D39AFD6D5F275ABA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_E5AD369E862BBC647E6FFD6D5F2739FA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_67E50E890FE0F139D39AFD6D5F275ABA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_0164B90591985E4F7867FD6D5F275D7F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_E5AD369E862BBC647E6FFD6D5F2739FA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_0164B90591985E4F7867FD6D5F275D7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_B14DBC015EAFBDAFB2BAFD6D5F27B7E5" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_E5AD369E862BBC647E6FFD6D5F2739FA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_B14DBC015EAFBDAFB2BAFD6D5F27B7E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_C0C94AC89BFA113E20A4FD6D5F27BC03" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_E5AD369E862BBC647E6FFD6D5F2739FA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_C0C94AC89BFA113E20A4FD6D5F27BC03" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_9380BF0E7752FBA1D8C3FD6D5F2715D2" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_E8D7E69D01B7568DC4B9FD6D5F26CBFD" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_9380BF0E7752FBA1D8C3FD6D5F2715D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_AE886AC43A2866520FD7FD6D5F276C70" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_9380BF0E7752FBA1D8C3FD6D5F2715D2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_AE886AC43A2866520FD7FD6D5F276C70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_11280B8A83F9419FF308FD6D5F287846" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_9380BF0E7752FBA1D8C3FD6D5F2715D2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_11280B8A83F9419FF308FD6D5F287846" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_9C438F5BE5E340AE9E92FD6D5F299019" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_9380BF0E7752FBA1D8C3FD6D5F2715D2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_9C438F5BE5E340AE9E92FD6D5F299019" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_45EAA3A10B3EEB73BF8EFD6D5F2BCF42" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_9380BF0E7752FBA1D8C3FD6D5F2715D2" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_45EAA3A10B3EEB73BF8EFD6D5F2BCF42" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationDetailsRsusWithPerformanceConditions" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C949A14E86137B17FED0FD6D5F0D43D4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_93378C5079FC383E4633FD6D5F0CCB04" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C949A14E86137B17FED0FD6D5F0D43D4" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_93378C5079FC383E4633FD6D5F0CCB04" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_70D320E0DB13BBCE5214FD6D5F0CBE07" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_93378C5079FC383E4633FD6D5F0CCB04" xlink:to="loc_us-gaap_AwardTypeAxis_70D320E0DB13BBCE5214FD6D5F0CBE07" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_934D1BC2FACDD31AA7C8FD6D5F0D178D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_70D320E0DB13BBCE5214FD6D5F0CBE07" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_934D1BC2FACDD31AA7C8FD6D5F0D178D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_934D1BC2FACDD31AA7C8FD6D5F0D178D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_70D320E0DB13BBCE5214FD6D5F0CBE07" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_934D1BC2FACDD31AA7C8FD6D5F0D178D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PerformanceSharesMember" xlink:label="loc_us-gaap_PerformanceSharesMember_8BF399073AC04E1B7ED5FD6D5F0D9296" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_934D1BC2FACDD31AA7C8FD6D5F0D178D" xlink:to="loc_us-gaap_PerformanceSharesMember_8BF399073AC04E1B7ED5FD6D5F0D9296" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_9DE8DA56EDB0318FB38CFD6D5F0DC79C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C949A14E86137B17FED0FD6D5F0D43D4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_9DE8DA56EDB0318FB38CFD6D5F0DC79C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_0F0F53292433FCB6A293FD6D5F0DAF8D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_9DE8DA56EDB0318FB38CFD6D5F0DC79C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_0F0F53292433FCB6A293FD6D5F0DAF8D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_AEA75B031A1675A4C0B4FD6D5F0D8418" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_9DE8DA56EDB0318FB38CFD6D5F0DC79C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_AEA75B031A1675A4C0B4FD6D5F0D8418" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_DDDA7E3C1E96AC0D9177FD6D5F0DD040" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_9DE8DA56EDB0318FB38CFD6D5F0DC79C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_DDDA7E3C1E96AC0D9177FD6D5F0DD040" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_45DE264E85D963F28C94FD6D5F0E2775" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_9DE8DA56EDB0318FB38CFD6D5F0DC79C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_45DE264E85D963F28C94FD6D5F0E2775" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_0E8F9DBC3CDEB112D480FD6D5F0E9D97" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C949A14E86137B17FED0FD6D5F0D43D4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_0E8F9DBC3CDEB112D480FD6D5F0E9D97" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_90384C096E24ED58EEFAFD6D5F0EFFF9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_0E8F9DBC3CDEB112D480FD6D5F0E9D97" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_90384C096E24ED58EEFAFD6D5F0EFFF9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_77E64D8D8DE2C8FFC324FD6D5F0E885C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_0E8F9DBC3CDEB112D480FD6D5F0E9D97" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_77E64D8D8DE2C8FFC324FD6D5F0E885C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_B6E7A22226786C8BD111FD6D5F0EFC6B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_0E8F9DBC3CDEB112D480FD6D5F0E9D97" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_B6E7A22226786C8BD111FD6D5F0EFC6B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_BB00963D397F3E359CB2FD6D5F0E3C78" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAdditionalDisclosuresAbstract_0E8F9DBC3CDEB112D480FD6D5F0E9D97" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_BB00963D397F3E359CB2FD6D5F0E3C78" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationDetailsStockOptionsRollforward" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5CDBFD99984D82DDA465FD6D5F5FC94C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5CDBFD99984D82DDA465FD6D5F5FC94C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VestingAxis" xlink:label="loc_us-gaap_VestingAxis_BC53824ABA6689D87217FD6D5F5FE8AF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5CDBFD99984D82DDA465FD6D5F5FC94C" xlink:to="loc_us-gaap_VestingAxis_BC53824ABA6689D87217FD6D5F5FE8AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VestingAxis_BC53824ABA6689D87217FD6D5F5FE8AF" xlink:to="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_VestingDomain" xlink:label="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VestingAxis_BC53824ABA6689D87217FD6D5F5FE8AF" xlink:to="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_A50overaperiodoftwoyearsfromthegrantdateMember" xlink:label="loc_tree_A50overaperiodoftwoyearsfromthegrantdateMember_5E469DE365A256053F2BFD6D5F5F4BB9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735" xlink:to="loc_tree_A50overaperiodoftwoyearsfromthegrantdateMember_5E469DE365A256053F2BFD6D5F5F4BB9" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_A33overaperiodofthreeyearsfromthegrantdateMember" xlink:label="loc_tree_A33overaperiodofthreeyearsfromthegrantdateMember_E3FA675E68A048F63457FD6D5F5FB974" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735" xlink:to="loc_tree_A33overaperiodofthreeyearsfromthegrantdateMember_E3FA675E68A048F63457FD6D5F5FB974" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_A25overaperiodoffouryearsfromthegrantdateMember" xlink:label="loc_tree_A25overaperiodoffouryearsfromthegrantdateMember_E16B76364B72B4C78BD0FD6D5F5FBC34" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VestingDomain_B8D854AB42E79ECB498AFD6D5F5F4735" xlink:to="loc_tree_A25overaperiodoffouryearsfromthegrantdateMember_E16B76364B72B4C78BD0FD6D5F5FBC34" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_9C2724292F00D3A524FAFD6D5F6012AF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5CDBFD99984D82DDA465FD6D5F5FC94C" xlink:to="loc_us-gaap_RangeAxis_9C2724292F00D3A524FAFD6D5F6012AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_248F5E869E537CA79A90FD6D5F60D7BD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_9C2724292F00D3A524FAFD6D5F6012AF" xlink:to="loc_us-gaap_RangeMember_248F5E869E537CA79A90FD6D5F60D7BD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_248F5E869E537CA79A90FD6D5F60D7BD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_9C2724292F00D3A524FAFD6D5F6012AF" xlink:to="loc_us-gaap_RangeMember_248F5E869E537CA79A90FD6D5F60D7BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_14913DF87801465BAF2AFD6D5F605C8F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_248F5E869E537CA79A90FD6D5F60D7BD" xlink:to="loc_us-gaap_MinimumMember_14913DF87801465BAF2AFD6D5F605C8F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_14395AB31DF7B25F28F0FD6D5F60B9B3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_248F5E869E537CA79A90FD6D5F60D7BD" xlink:to="loc_us-gaap_MaximumMember_14395AB31DF7B25F28F0FD6D5F60B9B3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_59040C167AAB6D14CC7AFD6D5F60B63E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5CDBFD99984D82DDA465FD6D5F5FC94C" xlink:to="loc_us-gaap_AwardTypeAxis_59040C167AAB6D14CC7AFD6D5F60B63E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_59040C167AAB6D14CC7AFD6D5F60B63E" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_59040C167AAB6D14CC7AFD6D5F60B63E" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockCompensationPlanMember" xlink:label="loc_us-gaap_StockCompensationPlanMember_3F5305362C8ED45124E1FD6D5F604CFA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD" xlink:to="loc_us-gaap_StockCompensationPlanMember_3F5305362C8ED45124E1FD6D5F604CFA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_2E530DE5083EE838CDEEFD6D5F6012E1" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD" xlink:to="loc_us-gaap_EmployeeStockOptionMember_2E530DE5083EE838CDEEFD6D5F6012E1" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_EmployeeStockOption2Member" xlink:label="loc_tree_EmployeeStockOption2Member_3803A18DF788AA1E944AFD6D5F608C8C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD" xlink:to="loc_tree_EmployeeStockOption2Member_3803A18DF788AA1E944AFD6D5F608C8C" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_PerformanceOptionsMember" xlink:label="loc_tree_PerformanceOptionsMember_4832F9EE612F2088BFE0FD6D5F613C4A" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_F9EADE4B49F214A07689FD6D5F6036AD" xlink:to="loc_tree_PerformanceOptionsMember_4832F9EE612F2088BFE0FD6D5F613C4A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_5761D8E4185C70F067AEFD6D5F61BBFD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_5761D8E4185C70F067AEFD6D5F61BBFD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_85F16562087BF0330EB6FD6D5F6121BA" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_85F16562087BF0330EB6FD6D5F6121BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_F32664ABAEDC70704389FD6D5F6126DA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_F32664ABAEDC70704389FD6D5F6126DA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E30C0E8B7DCF0A003DD9FD96A8331F62" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E30C0E8B7DCF0A003DD9FD96A8331F62" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_23B2B812C42641DB7C9EFD6D5F61B4F6" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod_23B2B812C42641DB7C9EFD6D5F61B4F6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_5E6CE44A60CA91EAA63CFD6D5F62EA58" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_218FBFE87AD13687DBB7FD6D5F613EA3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_5E6CE44A60CA91EAA63CFD6D5F62EA58" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7614CD363047B1FFF682FD6D5F67C41E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_7614CD363047B1FFF682FD6D5F67C41E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_A874069E8CC14863854AFD6D5F6785C0" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_A874069E8CC14863854AFD6D5F6785C0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_2F25B386080685127114FD6D5F67110B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_2F25B386080685127114FD6D5F67110B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_CE1636F300FDAEDCCBA2FD6D5F67BDCC" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_CE1636F300FDAEDCCBA2FD6D5F67BDCC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_1460C6E98B94967AAB00FD6D5F675A5F" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice_1460C6E98B94967AAB00FD6D5F675A5F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_327D98D5C33F16313D27FD6D5F6803CF" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_6CCBB7E03634EB262908FD6D5F629FAA" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_327D98D5C33F16313D27FD6D5F6803CF" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract" xlink:label="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_24CD6D9415E2DDBE68C3FD6D5F68771D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:to="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_24CD6D9415E2DDBE68C3FD6D5F68771D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_01876805262093576CC3FD6D5F684E13" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_24CD6D9415E2DDBE68C3FD6D5F68771D" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_01876805262093576CC3FD6D5F684E13" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_B686D06547B9036969E8FD6D5F6872CF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsWeightedAverageRemainingContractualTermAbstract_24CD6D9415E2DDBE68C3FD6D5F68771D" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_B686D06547B9036969E8FD6D5F6872CF" xlink:type="arc" />
    <link:loc xlink:href="tree-20180331.xsd#tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:label="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_265B4EE436E4DA16375CFD6D5F68E866" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:to="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_265B4EE436E4DA16375CFD6D5F68E866" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_901AF0BCAFF5CAF87AECFD6D5F68D8A6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_265B4EE436E4DA16375CFD6D5F68E866" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_901AF0BCAFF5CAF87AECFD6D5F68D8A6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_A486CBCF3AF9E781ADF6FD6D5F68AC4D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_tree_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_265B4EE436E4DA16375CFD6D5F68E866" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_A486CBCF3AF9E781ADF6FD6D5F68AC4D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4C13CF067717DB693531FD6D5F61509A" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaap_SharePrice_02750F38BE404D26DE66FD6D5F61A31A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_SharePrice_02750F38BE404D26DE66FD6D5F61A31A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_E99FC0D7004249F3999CFD6D5F682DD3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_E99FC0D7004249F3999CFD6D5F682DD3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_5D54E46B468FF15885A3FD6D5F69FB9D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_5D54E46B468FF15885A3FD6D5F69FB9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermSimplifiedMethod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermSimplifiedMethod_735B12DDA194AFE0B8E2FD6D5F69676A" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedTermSimplifiedMethod_735B12DDA194AFE0B8E2FD6D5F69676A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_0712B8609C2A28096470FD6D5F693195" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_0712B8609C2A28096470FD6D5F693195" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_497E2896BAD65EF7E6D3FD6D5F6958DD" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMinimum_497E2896BAD65EF7E6D3FD6D5F6958DD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_7DDDC71402EA6AB6DA7BFD6D5F69594F" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum_7DDDC71402EA6AB6DA7BFD6D5F69594F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_D6EA8AAE73AAA7276786FD6D5F690C2E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMinimum_D6EA8AAE73AAA7276786FD6D5F690C2E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_4DB2D71BEAE3E73E34EFFD6D5F697FC2" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRateMaximum_4DB2D71BEAE3E73E34EFFD6D5F697FC2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_49A45262C9331B4BDAC3FD6D5F690982" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsAndMethodologyAbstract_F1B2A4AC7EA45EA7FCFCFD6D5F680A70" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendPayments_49A45262C9331B4BDAC3FD6D5F690982" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationNote" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.tree.com/role/StockBasedCompensationTables" xlink:type="extended" />
</link:linkbase>





