Worldwide, Thachai (Thachai 
, ธชัย , ทะไชย ) is a very rare mostly male, but seldom female given name. The first name Thachai is habitual in Thailand, where it is a very rare largely masculine, but infrequently feminine name, and India, where it is an extremely rare male name. More frequently, Thachai is the last name as well as the forename.