perfidy
4 synonyms for perfidy, grouped by meaning and by how common each one is.
Noun — An act of breaking a promise or betraying someone's trust.
Synonyms
Less common
Still standard English, but they carry more weight.
Rare, literary or technical
Precise, but they will stand out — check the sense before using one.
Etymology
From Middle French perfidie, from Latin perfidia from perfidus (“faithless, treacherous, false”), from fides (“faith”); related to, for example, English fidelity.
Full origin of perfidy →