Proto-Turkic *kugu

→ Southern Altai куу (inherited)

→ Shor қуу (inherited)

→ Kazakh аққу (derived)

→ Old Turkic 𐰴𐰆𐰍𐰆 (inherited)

→ Turkmen guw (inherited)

→ Turkish kuğu (inherited)

→ Tuvan куу (inherited)