n.; pl.Perfidies [ L. perfidia, fr. L. perfidus faithless; per (cf. Skr. parā away) + fides faith: cf. F. perfidie. See Faith. ] The act of violating faith or allegiance; violation of a promise or vow, or of trust reposed; faithlessness; treachery. [ 1913 Webster ]
The ambition and perfidy of tyrants. Macaulay. [ 1913 Webster ]
His perfidy to this sacred engagement. DeQuincey. [ 1913 Webster ]