Family name Hadjak (Hadjak 
) , in the entire world, is a very rare cognomen. The surname Hadjak is characteristic of Croatia, where it is a rare surname, Indonesia, where it is a very rare surname, and Germany, where it is an extremely rare surname. Much less frequently, Hadjak is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Hadjak | Germany, Croatia, Indonesia, Philippines |