Cognomen ธาราสิทธิ์ (Tarasit 
, ธาราสิทธิ์ ) , all around the world, is a very rare last name. The family name ธาราสิทธิ์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. Much less frequently, ธาราสิทธิ์ is the forename as well as the last name.