n. 25B6; noun (poetic/literary) TREACHERY, duplicity, deceit, deceitfulness, disloyalty, infidelity, faithlessness, unfaithfulness, betrayal, treason, double-dealing, untrustworthiness, breach of trust; poetic/literary perfidiousness.
PERFIDY
Meaning of PERFIDY in English
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012