Cognomen Sīmā (สีมา 
, သိမ် 
, Sīmā) , around the globe, is quite a rare surname. The cognomen Sīmā is characteristic of South-eastern Asia, particularly Thailand, where it is quite a rare surname, and Myanmar, where it is a very rare surname. Much less frequently, Sīmā is the forename as well as the last name.