Webster 1913 Edition
Guilty of perfidy; violating good faith or vows; false to trust or confidence reposed; treacherous; faithless;
Involving, or characterized by, perfidy.“Involved in this perfidious fraud.”
Webster 1828 Edition
1.Violating good faith or vows; false to trust or confidence reposed; treacherous; as a perfidious agent; a perfidious friend. [See Perfidy.]
2.Proceeding from treachery, or consisting in breach of faith; as a perfidious act.
3.Guilty of violated allegiance; as a perfidious citizen; a man perfidious to his country.