I.faithless, dishonest, treacherous, false, perfidious (class.).
I. Of persons: “fallax, perfidiosus,” Cic. Pis. 27, 66: “perfidiosus et subdolus animo,” Tac. A. 16, 32.—Sup.: “omnium perfidiosissimus,” Cic. N. D. 3, 32, 80.—
II. Of inanim. and abstr. things: “amor,” Plaut. Cist. 1, 1, 73: “nihil perfidiosum et insidiosum et fallax in amicitiā,” Cic. Fam. 3, 10, 7; id. Rosc. Com. 6, 16.—Adv.: per-fĭdĭōsē , faithlessly, dishonestly, treacherously, perfidiously (rare but class.): “hercle istam rem judicasti perfidiose,” Plaut. Curc. 5, 3, 41: “multa perfidiose facta,” Cic. Rosc. Am. 40, 118: “perfidiose, crudeliter factum,” Auct. Her. 1, 5, 8.—Comp.: “perfidiosius rebellantes,” Suet. Aug. 21.