Last name อุ้ย (Ui 
, Ouay 
, อุ้ย) , globally, is quite a common cognomen. The cognomen อุ้ย is habitual in Macao, where it is quite a rare surname, Malaysia, and Oman, where it is a rare surname. Measured by absolute frequency, it is the most numerous in Indonesia, Malaysia, and China. Likewise, อุ้ย is the forename as well as the last name.