Cognomen Sinja (Sinja 
, سنجا 
, Синя 
) , in the world, is quite a rare family name. The last name Sinja is characteristic of Slovenia, where it is quite a rare surname, Kenya, where it is a rare surname, and Ukraine. In absolute terms, it most frequently occurs in Kenya, Ukraine, and Sudan. Also, Sinja is the forename as well as the last name.