Worldwide, Kosjak (Косяк , Kosjak ) is an extremely rare masculine forename. Much more frequently, Kosjak is the last name as well as the forename.
Косйак
Mr, Ms, Sven, Anna, Rene, Sonja, Jakob, Jurij, Erwin, Heide, Denise, Daniela, Jürgen, Christina, Katharina, and Christopher
, Kosjak 
) is an extremely rare masculine forename. Much more frequently, Kosjak is the last name as well as the forename.