Last name ธารสิทธิ์ (ธารสิทธิ์ 
) , in the entire world, is a very rare cognomen. The last name ธารสิทธิ์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. Very seldom, ธารสิทธิ์ is the forename as well as the last name.