Proto-Slavic *ǫsъ

→ Belarusian вус (inherited)

→ Czech vous (inherited)

→ Czech fous (inherited)

→ Czech fousy (inherited)

→ Lower Sorbian wusy (inherited)

→ Ancient Greek ἴονθος (cognate)

→ Polish fons (inherited)

→ Polish fus (derived)

→ Polish wąs (inherited)

→ Russian ус (inherited)

→ Serbo-Croatian us (inherited)

→ Slovak fúz (inherited)

→ Slovene vos (inherited)

→ Ukrainian вус (inherited)

→ Vilamovian wons (derived)