What does perfīdēns mean in Latin?

perfīdēns, a adjective, means “trusting greatly, confiding strongly”.

How do you pronounce perfīdēns?

In classical Latin, [pɛrˈfiː.dẽːs]; in ecclesiastical (church) Latin, [perˈfiː.dens].

adjectivethird-declension one-termination adjective

perfīdēns (genitive perfīdentis)

Classical[pɛrˈfiː.dẽːs]Ecclesiastical[perˈfiː.dens]

obsoleteone terminationtrusting greatly, confiding strongly
pugnandi arte perfidenstrusting greatly in the art of fighting358 CE – 360 CE, Aurelius Victor, De Caesaribus 17 (alternatively read as pervigens or perurgens)

singular
form	masculine	feminine	neuter
nominative	perfīdēns	perfīdēns	perfīdēns
genitive	perfīdentis	perfīdentis	perfīdentis
dative	perfīdentī	perfīdentī	perfīdentī
accusative	perfīdentem	perfīdentem	perfīdēns
ablative	perfīdentī perfīdente	perfīdentī perfīdente	perfīdentī perfīdente
vocative	perfīdēns	perfīdēns	perfīdēns

plural
form	masculine	feminine	neuter
nominative	perfīdentēs	perfīdentēs	perfīdentia
genitive	perfīdentium	perfīdentium	perfīdentium
dative	perfīdentibus	perfīdentibus	perfīdentibus
accusative	perfīdentīs perfīdentēs	perfīdentīs perfīdentēs	perfīdentia
ablative	perfīdentibus	perfīdentibus	perfīdentibus
vocative	perfīdentēs	perfīdentēs	perfīdentia

per-fīdens, entis, adj.,

I. trusting greatly, confiding strongly (post-class.): pugnandi arte perfidens, Aur. Vict. Caes. 17.

From per- (“very”) + fīdēns (“trusting, relying on”).