Reverse Dictionary: PERFIDIOUS

ADJECTIVES
1600 — FEDIFRAGOUS breaking a pledge or agreement, faithless, perfidious → obs.
1632 — PERFIDIATE perfidious, deceitful and untrustworthy → obs.
1911 — BREAK-FAITH perfidious, treacherous → Sc. (Bk.)

NOUNS
1250 — CULVERTSHIP villainy, treachery, perfidy → obs.