Family name Нагаичук (Нагаичук 
) , all over the world, is a very rare cognomen. The cognomen Нагаичук is characteristic of Eastern Europe, particularly Russia, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Нагаичук | Russia |
Nagaichuk, Nagaitchouk, and Nagaychuk