From Proto-Tai *triːwꟲ (“to carry (a bag)”). Cognate with Thai หิ้ว (hîu), Lao ຫິ້ວ (hiu), Shan ႁိဝ်ႈ (hīo), Bouyei riuc, Saek ริ̂ว.
riuj (Sawndip forms 𢲑 or 𭡻 or 𢩪, 1957–1982 spelling riuз)