From Proto-Tai *rɯːwꟲ (“to know”). Cognate with Thai รู้ (rúu), Northern Thai ᩁᩪ᩶, Isan ฮู้, Lao ຮູ້ (hū), Tai Dam ꪭꪴ꫁, Shan ႁူႉ (hṵ̂u), Ahom 𑜍𑜥 (rū) or 𑜍𑜤𑜈𑜫 (ruw), Zhuang rox, Saek รอ.
ᦣᦴᧉ • (huu²) (abstract noun ᦂᦱᧃᦣᦴᧉ or ᦩᦱᧄᦣᦴᧉ)