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English definition of “infidelity”

infidelity

noun [C or U]     /ˌɪn.fɪˈdel.ə.ti/ US  /-fəˈdel.ə.t̬i/
(an act of) having sex with someone who is not your husband, wife, or regular sexual partner, or (an example of) not being loyal or faithful: marital/sexual infidelity She could not forgive his many infidelities.Disloyalty, betrayal and treasonInfidelity in relationships
(Definition of infidelity noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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