<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
    <!-- Field: Doc-Info; Name: Generator; Value: GoFiler Complete; Version: 6.5a -->
    <!-- Field: Doc-Info; Name: VendorURI; Value: https://www.novaworks.com -->
    <!-- Field: Doc-Info; Name: Status; Value: 0x00000000 -->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#Cover" roleURI="http://hourloop.com/role/Cover" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#BalanceSheets" roleURI="http://hourloop.com/role/BalanceSheets" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#BalanceSheetsParenthetical" roleURI="http://hourloop.com/role/BalanceSheetsParenthetical" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#StatementsOfOperationsAndComprehensiveIncome" roleURI="http://hourloop.com/role/StatementsOfOperationsAndComprehensiveIncome" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#StatementsOfStockholdersEquity" roleURI="http://hourloop.com/role/StatementsOfStockholdersEquity" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#StatementsOfCashFlows" roleURI="http://hourloop.com/role/StatementsOfCashFlows" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#NatureOfOperationsAndSummaryOfSignificantAccountingPolicies" roleURI="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPolicies" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#RecentlyIssuedAndAdoptedAccountingPronouncements" roleURI="http://hourloop.com/role/RecentlyIssuedAndAdoptedAccountingPronouncements" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#Inventory" roleURI="http://hourloop.com/role/Inventory" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#PrepaidExpensesAndOtherCurrentAssets" roleURI="http://hourloop.com/role/PrepaidExpensesAndOtherCurrentAssets" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#PropertyAndEquipment" roleURI="http://hourloop.com/role/PropertyAndEquipment" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#AccountsPayableAndCreditCardsPayable" roleURI="http://hourloop.com/role/AccountsPayableAndCreditCardsPayable" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#Short-termLoan" roleURI="http://hourloop.com/role/Short-termLoan" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#AccruedExpensesAndOtherCurrentLiabilities" roleURI="http://hourloop.com/role/AccruedExpensesAndOtherCurrentLiabilities" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#Leases" roleURI="http://hourloop.com/role/Leases" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#RelatedPartyBalancesAndTransactions" roleURI="http://hourloop.com/role/RelatedPartyBalancesAndTransactions" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#DisaggregationOfRevenues" roleURI="http://hourloop.com/role/DisaggregationOfRevenues" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#IncomeTax" roleURI="http://hourloop.com/role/IncomeTax" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#StockholdersEquity" roleURI="http://hourloop.com/role/StockholdersEquity" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#CommitmentsAndContingencies" roleURI="http://hourloop.com/role/CommitmentsAndContingencies" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#SubsequentEvents" roleURI="http://hourloop.com/role/SubsequentEvents" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesPolicies" roleURI="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesPolicies" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesTables" roleURI="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#InventoryTables" roleURI="http://hourloop.com/role/InventoryTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#PrepaidExpensesAndOtherCurrentAssetsTables" roleURI="http://hourloop.com/role/PrepaidExpensesAndOtherCurrentAssetsTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#PropertyAndEquipmentTables" roleURI="http://hourloop.com/role/PropertyAndEquipmentTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#AccountsPayableAndCreditCardsPayableTables" roleURI="http://hourloop.com/role/AccountsPayableAndCreditCardsPayableTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesTables" roleURI="http://hourloop.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#LeasesTables" roleURI="http://hourloop.com/role/LeasesTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#DisaggregationOfRevenuesTables" roleURI="http://hourloop.com/role/DisaggregationOfRevenuesTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#IncomeTaxTables" roleURI="http://hourloop.com/role/IncomeTaxTables" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfForeignCurrencyExchangeRatesDetails" roleURI="http://hourloop.com/role/ScheduleOfForeignCurrencyExchangeRatesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesDetailsNarrative" roleURI="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfInventoryDetails" roleURI="http://hourloop.com/role/ScheduleOfInventoryDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#InventoryDetailsNarrative" roleURI="http://hourloop.com/role/InventoryDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetails" roleURI="http://hourloop.com/role/ScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#PrepaidExpensesAndOtherCurrentAssetsDetailsNarrative" roleURI="http://hourloop.com/role/PrepaidExpensesAndOtherCurrentAssetsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfPropertyAndEquipmentDetails" roleURI="http://hourloop.com/role/ScheduleOfPropertyAndEquipmentDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#PropertyAndEquipmentDetailsNarrative" roleURI="http://hourloop.com/role/PropertyAndEquipmentDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfAccountsPayableAndCreditCardsPayableDetails" roleURI="http://hourloop.com/role/ScheduleOfAccountsPayableAndCreditCardsPayableDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#AccountsPayableAndCreditCardsPayableDetailsNarrative" roleURI="http://hourloop.com/role/AccountsPayableAndCreditCardsPayableDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#Short-termLoanDetailsNarrative" roleURI="http://hourloop.com/role/Short-termLoanDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesDetails" roleURI="http://hourloop.com/role/ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesDetailsNarrative" roleURI="http://hourloop.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfOperatingLeasesCostDetails" roleURI="http://hourloop.com/role/ScheduleOfOperatingLeasesCostDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfOperatingLeaseLiabilitiesDetails" roleURI="http://hourloop.com/role/ScheduleOfOperatingLeaseLiabilitiesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#LeasesDetailsNarrative" roleURI="http://hourloop.com/role/LeasesDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#RelatedPartyBalancesAndTransactionsDetailsNarrative" roleURI="http://hourloop.com/role/RelatedPartyBalancesAndTransactionsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfRevenueDetails" roleURI="http://hourloop.com/role/ScheduleOfRevenueDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfEffectiveTaxRateReconciliationDetails" roleURI="http://hourloop.com/role/ScheduleOfEffectiveTaxRateReconciliationDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfTaxExpenseSummaryDetails" roleURI="http://hourloop.com/role/ScheduleOfTaxExpenseSummaryDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#ScheduleOfDeferredTaxAssetsAndLiabilitiesDetails" roleURI="http://hourloop.com/role/ScheduleOfDeferredTaxAssetsAndLiabilitiesDetails" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#IncomeTaxDetailsNarrative" roleURI="http://hourloop.com/role/IncomeTaxDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#StockholdersEquityDetailsNarrative" roleURI="http://hourloop.com/role/StockholdersEquityDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="hour-20260331.xsd#SubsequentEventsDetailsNarrative" roleURI="http://hourloop.com/role/SubsequentEventsDetailsNarrative" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#PvpExecutiveCategoriesOnly" roleURI="http://xbrl.sec.gov/ecd/role/PvpExecutiveCategoriesOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#PvpAdjustmentsOnly" roleURI="http://xbrl.sec.gov/ecd/role/PvpAdjustmentsOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#IndividualsOnly" roleURI="http://xbrl.sec.gov/ecd/role/IndividualsOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#AwardTypeOnly" roleURI="http://xbrl.sec.gov/ecd/AwardTypeOnly" />
    <link:roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2026/ecd-2026.xsd#TradingArrangmentsOnly" roleURI="http://xbrl.sec.gov/ecd/role/TradingArrangementsOnly" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#notAll" arcroleURI="http://xbrl.org/int/dim/arcrole/notAll" />
    <link:arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/Cover" xlink:title="00000001 - Document - Cover" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/BalanceSheets" xlink:title="00000002 - Statement - Consolidated Balance Sheets (Unaudited)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="loc_us-gaapScheduleOfDefinedBenefitPlansDisclosuresTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaapAssetsAbstract_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapAssetsAbstract_50" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaapAssetsCurrentAbstract_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_50" xlink:to="loc_us-gaapAssetsCurrentAbstract_50" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Cash" xlink:label="loc_us-gaapCash_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_50" xlink:to="loc_us-gaapCash_50" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaapAccountsReceivableNetCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_50" xlink:to="loc_us-gaapAccountsReceivableNetCurrent_50" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaapInventoryNet_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_50" xlink:to="loc_us-gaapInventoryNet_50" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_50" xlink:to="loc_us-gaapPrepaidExpenseAndOtherAssetsCurrent_50" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaapAssetsCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsCurrentAbstract_50" xlink:to="loc_us-gaapAssetsCurrent_50" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaapPropertyPlantAndEquipmentNet_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_50" xlink:to="loc_us-gaapPropertyPlantAndEquipmentNet_50" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="loc_us-gaapDeferredIncomeTaxAssetsNet_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_50" xlink:to="loc_us-gaapDeferredIncomeTaxAssetsNet_50" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaapOperatingLeaseRightOfUseAsset_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_50" xlink:to="loc_us-gaapOperatingLeaseRightOfUseAsset_50" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsNoncurrent" xlink:label="loc_us-gaapAssetsNoncurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_50" xlink:to="loc_us-gaapAssetsNoncurrent_50" xlink:type="arc" order="10" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="loc_us-gaapAssets_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsAbstract_50" xlink:to="loc_us-gaapAssets_50" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDefinedBenefitPlanDisclosureLineItems" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaapLiabilitiesCurrentAbstract_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:to="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:type="arc" order="13" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaapAccountsPayableCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapAccountsPayableCurrent_50" xlink:type="arc" order="14" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_CreditCardsPayable" xlink:label="loc_HOURCreditCardsPayable_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_HOURCreditCardsPayable_50" xlink:type="arc" order="15" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LinesOfCreditCurrent" xlink:label="loc_us-gaapLinesOfCreditCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapLinesOfCreditCurrent_50" xlink:type="arc" order="16" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapOperatingLeaseLiabilityCurrent_50" xlink:type="arc" order="17" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedIncomeTaxesCurrent" xlink:label="loc_us-gaapAccruedIncomeTaxesCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapAccruedIncomeTaxesCurrent_50" xlink:type="arc" order="18" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapAccruedLiabilitiesAndOtherLiabilities_50" xlink:type="arc" order="19" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaapOtherLiabilitiesCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapOtherLiabilitiesCurrent_50" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaapLiabilitiesCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesCurrentAbstract_50" xlink:to="loc_us-gaapLiabilitiesCurrent_50" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsNoncurrentAbstract" xlink:label="loc_us-gaapAssetsNoncurrentAbstract_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:to="loc_us-gaapAssetsNoncurrentAbstract_50" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaapOperatingLeaseLiabilityNoncurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_50" xlink:to="loc_us-gaapOperatingLeaseLiabilityNoncurrent_50" xlink:type="arc" order="23" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxesAndOtherTaxLiabilitiesNoncurrent" xlink:label="loc_us-gaapDeferredIncomeTaxesAndOtherTaxLiabilitiesNoncurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_50" xlink:to="loc_us-gaapDeferredIncomeTaxesAndOtherTaxLiabilitiesNoncurrent_50" xlink:type="arc" order="24" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrent" xlink:label="loc_us-gaapLiabilitiesNoncurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAssetsNoncurrentAbstract_50" xlink:to="loc_us-gaapLiabilitiesNoncurrent_50" xlink:type="arc" order="25" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaapLiabilities_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:to="loc_us-gaapLiabilities_50" xlink:type="arc" order="26" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaapCommitmentsAndContingencies_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:to="loc_us-gaapCommitmentsAndContingencies_50" xlink:type="arc" order="27" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaapStockholdersEquityAbstract_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:to="loc_us-gaapStockholdersEquityAbstract_50" xlink:type="arc" order="28" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaapPreferredStockValue_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_50" xlink:to="loc_us-gaapPreferredStockValue_50" xlink:type="arc" order="29" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaapCommonStockValue_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_50" xlink:to="loc_us-gaapCommonStockValue_50" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaapAdditionalPaidInCapital_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_50" xlink:to="loc_us-gaapAdditionalPaidInCapital_50" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaapRetainedEarningsAccumulatedDeficit_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_50" xlink:to="loc_us-gaapRetainedEarningsAccumulatedDeficit_50" xlink:type="arc" order="32" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_50" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeLossNetOfTax_50" xlink:type="arc" order="33" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStockholdersEquityAbstract_50" xlink:to="loc_us-gaapStockholdersEquity_50" xlink:type="arc" order="34" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaapLiabilitiesAndStockholdersEquity_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLiabilitiesAndStockholdersEquityAbstract_50" xlink:to="loc_us-gaapLiabilitiesAndStockholdersEquity_50" xlink:type="arc" order="35" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/BalanceSheetsParenthetical" xlink:title="00000003 - Statement - Consolidated Balance Sheets (Unaudited) (Parenthetical)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/StatementsOfOperationsAndComprehensiveIncome" xlink:title="00000004 - Statement - Consolidated Statements of Operations and Comprehensive Income (Unaudited)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/StatementsOfStockholdersEquity" xlink:title="00000005 - Statement - Consolidated Statements of Stockholders&apos; Equity (Unaudited)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaapStatementLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaapStatementTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStatementTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaapStatementEquityComponentsAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapStatementTable" xlink:to="loc_us-gaapStatementEquityComponentsAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaapEquityComponentDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapStatementEquityComponentsAxis" xlink:to="loc_us-gaapEquityComponentDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaapCommonStockMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapCommonStockMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaapAdditionalPaidInCapitalMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAdditionalPaidInCapitalMember_10" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaapRetainedEarningsMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapRetainedEarningsMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapEquityComponentDomain" xlink:to="loc_us-gaapAccumulatedOtherComprehensiveIncomeMember_30" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaapStockholdersEquity_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockholdersEquity_60" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaapSharesOutstanding_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapSharesOutstanding_60" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaapStockIssuedDuringPeriodValueShareBasedCompensation_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodValueShareBasedCompensation_60" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaapStockIssuedDuringPeriodSharesShareBasedCompensation_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapStockIssuedDuringPeriodSharesShareBasedCompensation_60" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax" xlink:label="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax_60" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaapNetIncomeLoss_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapStatementLineItems" xlink:to="loc_us-gaapNetIncomeLoss_60" xlink:type="arc" order="6" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/StatementsOfCashFlows" xlink:title="00000006 - Statement - Consolidated Statements of Cash Flows (Unaudited)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPolicies" xlink:title="999012 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/RecentlyIssuedAndAdoptedAccountingPronouncements" xlink:title="999013 - Disclosure - Recently Issued and Adopted Accounting Pronouncements" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/Inventory" xlink:title="999014 - Disclosure - Inventory" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/PrepaidExpensesAndOtherCurrentAssets" xlink:title="999015 - Disclosure - Prepaid Expenses and Other Current Assets" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/PropertyAndEquipment" xlink:title="999016 - Disclosure - Property and Equipment" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/AccountsPayableAndCreditCardsPayable" xlink:title="999017 - Disclosure - Accounts Payable and Credit Cards Payable" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/Short-termLoan" xlink:title="999018 - Disclosure - Short-Term Loan" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/AccruedExpensesAndOtherCurrentLiabilities" xlink:title="999019 - Disclosure - Accrued Expenses and Other Current Liabilities" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/Leases" xlink:title="999020 - Disclosure - Leases" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/RelatedPartyBalancesAndTransactions" xlink:title="999021 - Disclosure - Related Party Balances and Transactions" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/DisaggregationOfRevenues" xlink:title="999022 - Disclosure - Disaggregation of Revenues" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/IncomeTax" xlink:title="999023 - Disclosure - Income Tax" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/StockholdersEquity" xlink:title="999024 - Disclosure - Stockholders&#8217; Equity" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/CommitmentsAndContingencies" xlink:title="999025 - Disclosure - Commitments and Contingencies" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/SubsequentEvents" xlink:title="999026 - Disclosure - Subsequent Events" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesPolicies" xlink:title="999027 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies (Policies)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesTables" xlink:title="999028 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/InventoryTables" xlink:title="999029 - Disclosure - Inventory (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/PrepaidExpensesAndOtherCurrentAssetsTables" xlink:title="999030 - Disclosure - Prepaid Expenses and Other Current Assets (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/PropertyAndEquipmentTables" xlink:title="999031 - Disclosure - Property and Equipment (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/AccountsPayableAndCreditCardsPayableTables" xlink:title="999032 - Disclosure - Accounts Payable and Credit Cards Payable (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:title="999033 - Disclosure - Accrued Expenses and Other Current Liabilities (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/LeasesTables" xlink:title="999034 - Disclosure - Leases (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/DisaggregationOfRevenuesTables" xlink:title="999035 - Disclosure - Disaggregation of Revenues (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/IncomeTaxTables" xlink:title="999036 - Disclosure - Income Tax (Tables)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfForeignCurrencyExchangeRatesDetails" xlink:title="999037 - Disclosure - Schedule of Foreign Currency Exchange Rates (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaapAwardTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="loc_us-gaapAwardTypeAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardTypeAxis" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapAwardTypeAxis" xlink:to="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_PeriodNTDUSDExchangeRateMember" xlink:label="loc_HOURPeriodNTDUSDExchangeRateMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_HOURPeriodNTDUSDExchangeRateMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_PeriodAverageNTDUSDExchangeRateMember" xlink:label="loc_HOURPeriodAverageNTDUSDExchangeRateMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_HOURPeriodAverageNTDUSDExchangeRateMember_30" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyExchangeRateTranslation1" xlink:label="loc_us-gaapForeignCurrencyExchangeRateTranslation1_70" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="loc_us-gaapForeignCurrencyExchangeRateTranslation1_70" xlink:type="arc" order="0" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/NatureOfOperationsAndSummaryOfSignificantAccountingPoliciesDetailsNarrative" xlink:title="999038 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductInformationLineItems" xlink:label="loc_us-gaapProductInformationLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfProductInformationTable" xlink:label="loc_us-gaapScheduleOfProductInformationTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapScheduleOfProductInformationTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapPropertyPlantAndEquipmentByTypeAxis" xlink:to="loc_us-gaapPropertyPlantAndEquipmentTypeDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComputerEquipmentMember" xlink:label="loc_us-gaapComputerEquipmentMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapPropertyPlantAndEquipmentTypeDomain" xlink:to="loc_us-gaapComputerEquipmentMember_30" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MajorCustomersAxis" xlink:label="loc_srtMajorCustomersAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_srtMajorCustomersAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtMajorCustomersAxis" xlink:to="loc_srtNameOfMajorCustomerDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srtNameOfMajorCustomerDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtMajorCustomersAxis" xlink:to="loc_srtNameOfMajorCustomerDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_CustomerMember" xlink:label="loc_HOURCustomerMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtNameOfMajorCustomerDomain" xlink:to="loc_HOURCustomerMember_50" xlink:type="arc" order="51" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaapConcentrationRiskByBenchmarkAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaapConcentrationRiskBenchmarkDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConcentrationRiskByBenchmarkAxis" xlink:to="loc_us-gaapConcentrationRiskBenchmarkDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SalesRevenueNetMember" xlink:label="loc_us-gaapSalesRevenueNetMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskBenchmarkDomain" xlink:to="loc_us-gaapSalesRevenueNetMember_50" xlink:type="arc" order="52" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaapConcentrationRiskByTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfProductInformationTable" xlink:to="loc_us-gaapConcentrationRiskByTypeAxis" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaapConcentrationRiskTypeDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapConcentrationRiskByTypeAxis" xlink:to="loc_us-gaapConcentrationRiskTypeDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaapConcentrationRiskTypeDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapConcentrationRiskByTypeAxis" xlink:to="loc_us-gaapConcentrationRiskTypeDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="loc_us-gaapCustomerConcentrationRiskMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapConcentrationRiskTypeDomain" xlink:to="loc_us-gaapCustomerConcentrationRiskMember_50" xlink:type="arc" order="53" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="loc_us-gaapNumberOfOperatingSegments_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapNumberOfOperatingSegments_80" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFDICInsuredAmount" xlink:label="loc_us-gaapCashFDICInsuredAmount_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapCashFDICInsuredAmount_80" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWriteDown" xlink:label="loc_us-gaapInventoryWriteDown_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapInventoryWriteDown_80" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfPropertyRepairsAndMaintenance" xlink:label="loc_us-gaapCostOfPropertyRepairsAndMaintenance_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapCostOfPropertyRepairsAndMaintenance_80" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="loc_us-gaapPropertyPlantAndEquipmentUsefulLife_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapPropertyPlantAndEquipmentUsefulLife_80" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" xlink:label="loc_us-gaapImpairmentOfLongLivedAssetsToBeDisposedOf_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapImpairmentOfLongLivedAssetsToBeDisposedOf_80" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_SalesReturnRate" xlink:label="loc_HOURSalesReturnRate_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_HOURSalesReturnRate_80" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_ShippingAndHandlingCosts" xlink:label="loc_HOURShippingAndHandlingCosts_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_HOURShippingAndHandlingCosts_80" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskCustomer" xlink:label="loc_us-gaapConcentrationRiskCustomer_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapConcentrationRiskCustomer_80" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="loc_us-gaapConcentrationRiskPercentage1_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapConcentrationRiskPercentage1_80" xlink:type="arc" order="9" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdvertisingExpense" xlink:label="loc_us-gaapAdvertisingExpense_80" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapProductInformationLineItems" xlink:to="loc_us-gaapAdvertisingExpense_80" xlink:type="arc" order="10" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfInventoryDetails" xlink:title="999039 - Disclosure - Schedule of Inventory (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/InventoryDetailsNarrative" xlink:title="999040 - Disclosure - Inventory (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetails" xlink:title="999041 - Disclosure - Schedule of Prepaid Expenses and Other Current Assets (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/PrepaidExpensesAndOtherCurrentAssetsDetailsNarrative" xlink:title="999042 - Disclosure - Prepaid Expenses and Other Current Assets (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfPropertyAndEquipmentDetails" xlink:title="999043 - Disclosure - Schedule of Property and Equipment (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/PropertyAndEquipmentDetailsNarrative" xlink:title="999044 - Disclosure - Property and Equipment (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfAccountsPayableAndCreditCardsPayableDetails" xlink:title="999045 - Disclosure - Schedule of Accounts Payable and Credit Cards Payable (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/AccountsPayableAndCreditCardsPayableDetailsNarrative" xlink:title="999046 - Disclosure - Accounts Payable and Credit Cards Payable (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/Short-termLoanDetailsNarrative" xlink:title="999047 - Disclosure - Short-Term Loan (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaapLineOfCreditFacilityLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityTable" xlink:label="loc_us-gaapLineOfCreditFacilityTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCreditFacilityTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaapCreditFacilityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapCreditFacilityAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaapCreditFacilityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapCreditFacilityAxis" xlink:to="loc_us-gaapCreditFacilityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaapCreditFacilityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapCreditFacilityAxis" xlink:to="loc_us-gaapCreditFacilityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaapLineOfCreditMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapCreditFacilityDomain" xlink:to="loc_us-gaapLineOfCreditMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityAxis" xlink:label="loc_us-gaapLineOfCreditFacilityAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapLineOfCreditFacilityTable" xlink:to="loc_us-gaapLineOfCreditFacilityAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain" xlink:label="loc_us-gaapLineOfCreditFacilityLenderDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapLineOfCreditFacilityAxis" xlink:to="loc_us-gaapLineOfCreditFacilityLenderDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityLenderDomain" xlink:label="loc_us-gaapLineOfCreditFacilityLenderDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapLineOfCreditFacilityAxis" xlink:to="loc_us-gaapLineOfCreditFacilityLenderDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_TaishinInternationalBankMember" xlink:label="loc_HOURTaishinInternationalBankMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLenderDomain" xlink:to="loc_HOURTaishinInternationalBankMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaapLineOfCredit_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCredit_40" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xlink:label="loc_us-gaapLineOfCreditFacilityInterestRateAtPeriodEnd_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapLineOfCreditFacilityLineItems" xlink:to="loc_us-gaapLineOfCreditFacilityInterestRateAtPeriodEnd_40" xlink:type="arc" order="1" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:title="999048 - Disclosure - Schedule of Accrued Expenses and Other Current Liabilities (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetailsNarrative" xlink:title="999049 - Disclosure - Accrued Expenses and Other Current Liabilities (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfOperatingLeasesCostDetails" xlink:title="999050 - Disclosure - Schedule of Operating Leases Cost (Details)">
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_LesseeOperatingLeaseDescriptionLineItems" xlink:label="loc_HOURLesseeOperatingLeaseDescriptionLineItems" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_LesseeOperatingLeaseDescriptionTable" xlink:label="loc_HOURLesseeOperatingLeaseDescriptionTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_HOURLesseeOperatingLeaseDescriptionLineItems" xlink:to="loc_HOURLesseeOperatingLeaseDescriptionTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srtConsolidatedEntitiesAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_HOURLesseeOperatingLeaseDescriptionTable" xlink:to="loc_srtConsolidatedEntitiesAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srtConsolidatedEntitiesDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtConsolidatedEntitiesAxis" xlink:to="loc_srtConsolidatedEntitiesDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SubsidiariesMember" xlink:label="loc_srtSubsidiariesMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtConsolidatedEntitiesDomain" xlink:to="loc_srtSubsidiariesMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardDateAxis" xlink:label="loc_us-gaapAwardDateAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_HOURLesseeOperatingLeaseDescriptionTable" xlink:to="loc_us-gaapAwardDateAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardDateDomain" xlink:label="loc_us-gaapAwardDateDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapAwardDateAxis" xlink:to="loc_us-gaapAwardDateDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_JuneTwoThousandAndTwentyFiveToJuneTwoThousandAndTwentySevenMember" xlink:label="loc_HOURJuneTwoThousandAndTwentyFiveToJuneTwoThousandAndTwentySevenMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAwardDateDomain" xlink:to="loc_HOURJuneTwoThousandAndTwentyFiveToJuneTwoThousandAndTwentySevenMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_DecemberTwoThousandTwentyFiveToNovemberTwoThousandTwentyEightMember" xlink:label="loc_HOURDecemberTwoThousandTwentyFiveToNovemberTwoThousandTwentyEightMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapAwardDateDomain" xlink:to="loc_HOURDecemberTwoThousandTwentyFiveToNovemberTwoThousandTwentyEightMember_10" xlink:type="arc" order="12" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaapOperatingLeaseRightOfUseAsset_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURLesseeOperatingLeaseDescriptionLineItems" xlink:to="loc_us-gaapOperatingLeaseRightOfUseAsset_30" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xlink:label="loc_us-gaapOperatingLeaseWeightedAverageRemainingLeaseTerm1_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURLesseeOperatingLeaseDescriptionLineItems" xlink:to="loc_us-gaapOperatingLeaseWeightedAverageRemainingLeaseTerm1_30" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="loc_us-gaapOperatingLeaseWeightedAverageDiscountRatePercent_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURLesseeOperatingLeaseDescriptionLineItems" xlink:to="loc_us-gaapOperatingLeaseWeightedAverageDiscountRatePercent_30" xlink:type="arc" order="2" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfOperatingLeaseLiabilitiesDetails" xlink:title="999051 - Disclosure - Schedule of Operating Lease Liabilities (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/LeasesDetailsNarrative" xlink:title="999052 - Disclosure - Leases (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/RelatedPartyBalancesAndTransactionsDetailsNarrative" xlink:title="999053 - Disclosure - Related Party Balances and Transactions (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaapRelatedPartyTransactionLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaapRelatedPartyDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapRelatedPartyTransactionsByRelatedPartyAxis" xlink:to="loc_us-gaapRelatedPartyDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaapRelatedPartyMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyDomain" xlink:to="loc_us-gaapRelatedPartyMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilities" xlink:label="loc_us-gaapOtherLiabilities_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapOtherLiabilities_50" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentMaturityDate" xlink:label="loc_us-gaapDebtInstrumentMaturityDate_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapDebtInstrumentMaturityDate_50" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaapDebtInstrumentInterestRateStatedPercentage_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapDebtInstrumentInterestRateStatedPercentage_50" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_StockholderPayable" xlink:label="loc_HOURStockholderPayable_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_HOURStockholderPayable_50" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedBonusesCurrent" xlink:label="loc_us-gaapAccruedBonusesCurrent_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapAccruedBonusesCurrent_50" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfRelatedPartyDebt" xlink:label="loc_us-gaapRepaymentsOfRelatedPartyDebt_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapRelatedPartyTransactionLineItems" xlink:to="loc_us-gaapRepaymentsOfRelatedPartyDebt_50" xlink:type="arc" order="5" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfRevenueDetails" xlink:title="999054 - Disclosure - Schedule of Revenue (Details)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="loc_us-gaapDisaggregationOfRevenueLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:label="loc_us-gaapDisaggregationOfRevenueTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapDisaggregationOfRevenueLineItems" xlink:to="loc_us-gaapDisaggregationOfRevenueTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srtStatementGeographicalAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapDisaggregationOfRevenueTable" xlink:to="loc_srtStatementGeographicalAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srtSegmentGeographicalDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtStatementGeographicalAxis" xlink:to="loc_srtSegmentGeographicalDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srtSegmentGeographicalDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtStatementGeographicalAxis" xlink:to="loc_srtSegmentGeographicalDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AmericasMember" xlink:label="loc_srtAmericasMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtSegmentGeographicalDomain" xlink:to="loc_srtAmericasMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_InternationalMember" xlink:label="loc_HOURInternationalMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtSegmentGeographicalDomain" xlink:to="loc_HOURInternationalMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_OtherMember" xlink:label="loc_HOUROtherMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtSegmentGeographicalDomain" xlink:to="loc_HOUROtherMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDisaggregationOfRevenueLineItems" xlink:to="loc_us-gaapRevenueFromContractWithCustomerExcludingAssessedTax_90" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_DisaggregationOfRevenueSalesReturns" xlink:label="loc_HOURDisaggregationOfRevenueSalesReturns_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDisaggregationOfRevenueLineItems" xlink:to="loc_HOURDisaggregationOfRevenueSalesReturns_90" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_DisaggregationOfRevenueDiscounts" xlink:label="loc_HOURDisaggregationOfRevenueDiscounts_90" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapDisaggregationOfRevenueLineItems" xlink:to="loc_HOURDisaggregationOfRevenueDiscounts_90" xlink:type="arc" order="2" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfEffectiveTaxRateReconciliationDetails" xlink:title="999055 - Disclosure - Schedule of Effective Tax Rate Reconciliation (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfTaxExpenseSummaryDetails" xlink:title="999056 - Disclosure - Schedule of Tax Expense Summary (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/ScheduleOfDeferredTaxAssetsAndLiabilitiesDetails" xlink:title="999057 - Disclosure - Schedule of Deferred Tax Assets and Liabilities (Details)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/IncomeTaxDetailsNarrative" xlink:title="999058 - Disclosure - Income Tax (Details Narrative)" />
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/StockholdersEquityDetailsNarrative" xlink:title="999059 - Disclosure - Stockholders&#8217; Equity (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_StockholdersEquityNoteLineItems" xlink:label="loc_HOURStockholdersEquityNoteLineItems" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_StockholdersEquityNoteTable" xlink:label="loc_HOURStockholdersEquityNoteTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_HOURStockholdersEquityNoteTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srtTitleOfIndividualAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_HOURStockholdersEquityNoteTable" xlink:to="loc_srtTitleOfIndividualAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtTitleOfIndividualAxis" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtTitleOfIndividualAxis" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_SamLaiMember" xlink:label="loc_HOURSamLaiMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURSamLaiMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_MaggieYuMember" xlink:label="loc_HOURMaggieYuMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURMaggieYuMember_30" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_MichaelLennerMember" xlink:label="loc_HOURMichaelLennerMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURMichaelLennerMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_AlanGaoMember" xlink:label="loc_HOURAlanGaoMember_50" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURAlanGaoMember_50" xlink:type="arc" order="51" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_HillaryBuiMember" xlink:label="loc_HOURHillaryBuiMember_60" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURHillaryBuiMember_60" xlink:type="arc" order="61" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaapTypeOfArrangementAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_HOURStockholdersEquityNoteTable" xlink:to="loc_us-gaapTypeOfArrangementAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_ExecutiveEmploymentAgreementsOrDirectorAgreementsMember" xlink:label="loc_HOURExecutiveEmploymentAgreementsOrDirectorAgreementsMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:to="loc_HOURExecutiveEmploymentAgreementsOrDirectorAgreementsMember_20" xlink:type="arc" order="22" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaapPreferredStockSharesAuthorized_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapPreferredStockSharesAuthorized_280" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaapPreferredStockParOrStatedValuePerShare_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapPreferredStockParOrStatedValuePerShare_280" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="loc_us-gaapPreferredStockSharesIssued_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapPreferredStockSharesIssued_280" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaapPreferredStockSharesOutstanding_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapPreferredStockSharesOutstanding_280" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaapCommonStockSharesAuthorized_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapCommonStockSharesAuthorized_280" xlink:type="arc" order="4" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaapCommonStockParOrStatedValuePerShare_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapCommonStockParOrStatedValuePerShare_280" xlink:type="arc" order="5" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaapCommonStockSharesIssued_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapCommonStockSharesIssued_280" xlink:type="arc" order="6" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaapCommonStockSharesOutstanding_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapCommonStockSharesOutstanding_280" xlink:type="arc" order="7" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaapSharesIssued_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapSharesIssued_280" xlink:type="arc" order="8" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaapSharesIssuedPricePerShare_280" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_HOURStockholdersEquityNoteLineItems" xlink:to="loc_us-gaapSharesIssuedPricePerShare_280" xlink:type="arc" order="9" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://hourloop.com/role/SubsequentEventsDetailsNarrative" xlink:title="999060 - Disclosure - Subsequent Events (Details Narrative)">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems" xlink:label="loc_us-gaapSubsequentEventLineItems" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable" xlink:label="loc_us-gaapSubsequentEventTable" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xbrldt:contextElement="segment" xlink:from="loc_us-gaapSubsequentEventLineItems" xlink:to="loc_us-gaapSubsequentEventTable" xlink:type="arc" order="10" xbrldt:closed="true" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srtTitleOfIndividualAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapSubsequentEventTable" xlink:to="loc_srtTitleOfIndividualAxis" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srtTitleOfIndividualAxis" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_srtTitleOfIndividualAxis" xlink:to="loc_srtTitleOfIndividualWithRelationshipToEntityDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_SamLaiMember" xlink:label="loc_HOURSamLaiMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURSamLaiMember_0" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_MaggieYuMember" xlink:label="loc_HOURMaggieYuMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURMaggieYuMember_10" xlink:type="arc" order="11" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_MichaelLennerMember" xlink:label="loc_HOURMichaelLennerMember_20" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURMichaelLennerMember_20" xlink:type="arc" order="21" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_AlanGaoMember" xlink:label="loc_HOURAlanGaoMember_30" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURAlanGaoMember_30" xlink:type="arc" order="31" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_HillaryBuiMember" xlink:label="loc_HOURHillaryBuiMember_40" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srtTitleOfIndividualWithRelationshipToEntityDomain" xlink:to="loc_HOURHillaryBuiMember_40" xlink:type="arc" order="41" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfArrangementAxis" xlink:label="loc_us-gaapTypeOfArrangementAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapSubsequentEventTable" xlink:to="loc_us-gaapTypeOfArrangementAxis" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:label="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapTypeOfArrangementAxis" xlink:to="loc_us-gaapArrangementsAndNonarrangementTransactionsMember_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_ExecutiveEmploymentAgreementsOrDirectorAgreementsMember" xlink:label="loc_HOURExecutiveEmploymentAgreementsOrDirectorAgreementsMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapArrangementsAndNonarrangementTransactionsMember" xlink:to="loc_HOURExecutiveEmploymentAgreementsOrDirectorAgreementsMember_0" xlink:type="arc" order="2" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaapSubsequentEventTypeAxis" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaapSubsequentEventTable" xlink:to="loc_us-gaapSubsequentEventTypeAxis" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaapSubsequentEventTypeAxis" xlink:to="loc_us-gaapSubsequentEventTypeDomain" xlink:type="arc" order="20" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaapSubsequentEventTypeDomain_10" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xbrldt:contextElement="segment" xlink:from="loc_us-gaapSubsequentEventTypeAxis" xlink:to="loc_us-gaapSubsequentEventTypeDomain_10" xlink:type="arc" order="30" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaapSubsequentEventMember_0" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsequentEventTypeDomain" xlink:to="loc_us-gaapSubsequentEventMember_0" xlink:type="arc" order="3" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsequentEventLineItems" xlink:to="loc_us-gaapShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_120" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaapSharesIssuedPricePerShare_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsequentEventLineItems" xlink:to="loc_us-gaapSharesIssuedPricePerShare_120" xlink:type="arc" order="1" />
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivables" xlink:label="loc_us-gaapOtherReceivables_120" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapSubsequentEventLineItems" xlink:to="loc_us-gaapOtherReceivables_120" xlink:type="arc" order="2" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/ecd/role/PvpExecutiveCategoriesOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/ecd/role/PvpAdjustmentsOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/ecd/role/IndividualsOnly" />
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/ecd/AwardTypeOnly">
      <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_PeriodNTDUSDExchangeRateMember" xlink:label="loc_HOURPeriodNTDUSDExchangeRateMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_HOURPeriodNTDUSDExchangeRateMember" xlink:type="arc" order="0" />
      <link:loc xlink:type="locator" xlink:href="hour-20260331.xsd#HOUR_PeriodAverageNTDUSDExchangeRateMember" xlink:label="loc_HOURPeriodAverageNTDUSDExchangeRateMember" />
      <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaapShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="loc_HOURPeriodAverageNTDUSDExchangeRateMember" xlink:type="arc" order="10" />
    </link:definitionLink>
    <link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/ecd/role/TradingArrangementsOnly" />
</link:linkbase>
