Family name Kolsun (Kolsun 
, Кольсун 
) , in all the world, is a very rare cognomen. The cognomen Kolsun is characteristic of Canada, where it is a very rare surname, Ukraine, and the United States. In absolute terms, the name is most common in the United States, Russia, and Canada. Much less frequently, Kolsun is the forename as well as the last name.