Old French froc

← Old English rocc (cognate)

← German Rock (cognate)

← Proto-Germanic *hrukkaz (mention)

← Proto-Germanic *rukkaz (mention)

← Old High German hroch (cognate)

← Old High German roc (mention)

← Proto-Indo-European *rug(')- (mention)

← Old Saxon rok (cognate)

→ English frock (derived)

→ French froc (mention)

→ Middle French frocq (derived)

→ Dutch frak (derived)

→ Norman fro (inherited)

→ Polish frak (borrowed)