Family name Сиян (Sijan 
, Siyan 
, Siian 
) , around the world, is quite a common last name. The last name Сиян is habitual in Serbia, where it is quite a common surname, Qatar, where it is quite a rare surname, and Bosnia and Herzegovina. Measured by absolute frequency, it most frequently occurs in Bangladesh, Serbia, and India. Likewise, Сиян is the forename as well as the last name.