Cognomen וסטרמרק (וסטרמרק 
, Westermarck 
) , around the world, is a rare family name. The surname וסטרמרק is characteristic of Northern Europe, particularly Finland, where it is quite a rare surname, Estonia, where it is a rare surname, and Denmark, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| וסטרמרק | Israel |
| Westermarck | United States, Denmark, Estonia, Finland |