Cognomen Яук (Jauk 
, Yauk 
, Iauk 
) , across the world, is quite a rare family name. The last name Яук is characteristic of Austria, where it is quite a common surname, Slovenia, where it is quite a rare surname, and Croatia. In absolute terms, it most frequently occurs in Austria, India, and Germany. Very seldom, Яук is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Jauk | Germany, Austria, United States, India, Myanmar |
| Yauk | Indonesia, United States, India, Argentina, Myanmar |
| Iauk | Italy, Argentina, United States |
| Яук | Kyrgyzstan, Kazakhstan, Russia, Ukraine |