Italian fido

← Proto-Indo-European *bʰeydʰ- (root)

← Proto-Indo-European (inherited)

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

← Italian fidare (back-formation)

← Proto-Italic *feiðos (inherited)

← Latin fīdus (inherited)

→ English Fido (derived)

→ Italian infido (prefix)