From Proto-Tai *C̥.doːjᴬ (“mountain”). Cognate with Thai ดอย (dɔɔi), Lao ດອຍ (dǭi), Northern Thai ᨯᩬ᩠ᨿ, Khün ᨯᩭ, Lü ᦡᦾ (ḋoay), Tai Nüa ᥘᥩᥭ (loay), Ahom 𑜓𑜨𑜩 (doy) หรือ 𑜓𑜨𑜩𑜐𑜫 (doyñ), Zhuang ndoi.
လွႆ • (lǎui)