Latin perfidiosus

← Proto-Indo-European *bʰeydʰ- (root)

← Proto-Indo-European *per (derived)

← Proto-Indo-European *bʰeydʰ- (mention)

← Proto-Italic *feiðos (derived)

← Latin perfidia (suffix)

← Latin -ōsus (suffix)

← Latin perfidus (suffix)

← Latin -ia (suffix)

← Latin per (mention)

← Latin fidēs (mention)

→ Italian perfidioso (mention)