Cognate with Lao ຝ້າຍ (fāi), Northern Thai ᨺ᩶ᩣ᩠ᨿ, Lü ᦚᦻᧉ (ḟaay²), Tày phải, Bouyei waais, Zhuang faiq.
ฝ้าย • (fâai)