From Proto-Tai *C̥.dukᴰ (“bone”). Cognate with Thai ดูก (dùuk), Isan ดูก, Lao ດູກ (dūk) and later ກະດູກ (ka dūk), Shan *လုက်ႇ (*lùk) and later လုပ်ႇ (lùp), Lü ᦡᦳᧅᧈ (ḋuk¹), Tai Nüa ᥘᥧᥐᥴ (lúk). Compare Proto-Hlai *Cuɾɯːk (“bone”).
𑜓𑜤𑜀𑜫 (duk)