From Proto-Tai *χeːwꟲ (“fang”). Cognate with Thai เขี้ยว (kîao), Northern Thai ᨡ᩠᩶ᨿᩅ, Lao ແຂ້ວ (khǣu), Shan ၶဵဝ်ႈ (khāeo), Ahom 𑜁𑜢𑜈𑜫 (khiw), Zhuang heuj, Isan แข้ว.
ᥔᥥᥝᥲ (sèw) (1963 orthography ᥔᥥᥝ̀)