Cognomen Bosau (Bosau 
) , worldwide, is a rare last name. The cognomen Bosau is characteristic of Germany, where it is a rare surname, Indonesia, where it is a very rare surname, and the United States, where it is an extremely rare surname. Much less frequently, Bosau is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Bosau | Germany, France, United States, India, Indonesia |