From Proto-Tai *kajᴮ (“chicken”), from Middle Chinese 雞 (MC kej, “chicken”). Cognate with Thai ไก่ (gài), Northern Thai ᨠᩱ᩵ (kai), Lao ໄກ່ (kai), Lü ᦺᦂᧈ (k̇ay¹), Tai Dam ꪼꪀ꪿, Shan ၵႆႇ (kài), Tai Nüa ᥐᥭᥱ (kǎy), Aiton ကႝ (kay), Bouyei gais, Zhuang gaeq, Saek ไก.