Surname Zaionc (Zając 
, Zaionc 
, Зайонц 
) , in the entire world, is a common family name. The family name Zaionc is characteristic of Poland, where it is quite a common surname, Ireland, where it is a rare surname, and Ukraine. Not in comparison with a country's population, this name is the most popular in Eastern Europe, particularly Poland, Russia, and Ukraine.
| VARIANT | COUNTRY |
|---|---|
| Zając | Poland, Sweden, United States, United Kingdom, Germany |
| Zaionc | Brazil, United States, Poland |
| Зайонц | Russia, Ukraine |
| marek zaionc Ph.D. Uniwersytet Warszawski 1985 (b. 1953) |
|