perfĭdĭōsus — Lewis & Short
perfĭdĭōsus, a, um, adj.perfidia,
fallax, perfidiosus,Cic. Pis. 27, 66:
perfidiosus et subdolus animo,Tac. A. 16, 32.—Sup.:
omnium perfidiosissimus,Cic. N. D. 3, 32, 80.—
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.