Cognomen Deian (Деян 
, Deian 
, Дейан ) , in all the world, is a rare surname. The last name Deian is characteristic of Eastern Europe, particularly Bulgaria, where it is quite a rare surname, Romania, where it is a rare surname, and Belarus, where it is a very rare surname. In absolute terms, this name is the most popular in Bulgaria, Romania, and Pakistan. More frequently, Deian is the forename as well as the last name.