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English definition of “unfaithful”


adjective uk   /ʌnˈfeɪθ.fəl/ us  
having a sexual relationship or experience with a person who is not your husband, wife, or usual sexual partner: If a man was unfaithful to me I'd leave him no matter what the circumstances.Disloyalty, betrayal and treasonInfidelity in relationships
noun [U] uk   /-nəs/ us  
Disloyalty, betrayal and treasonInfidelity in relationships
(Definition of unfaithful from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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