Family name Sahajdak (Sahajdak 
, Сагайдак 
) , around the world, is quite a common cognomen. The last name Sahajdak is habitual in Ukraine, where it is quite a common surname, Kazakhstan, where it is quite a rare surname, and Russia. Much less frequently, Sahajdak is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sahajdak | Czechia, Australia, United States, Poland, France |
| Сагайдак | Azerbaijan, Kazakhstan, Russia, Kyrgyzstan, Ukraine |