Old Norse fýri

← Old English fyrhþ (cognate)

← English forest (mention)

← Proto-Germanic *furhiją (inherited)

← Old High German forst (cognate)

← Proto-Indo-European *perkʷ- (derived)

→ English fir (derived)

→ English quercus (derived(en/la))

→ English frith (cognate)

→ Old English furh (mention)

→ Middle English firre (borrowed)