Family name Cosny (Cosny 
) , in all the world, is a very rare cognomen. The last name Cosny is habitual in Singapore, where it is a rare surname, Myanmar, where it is a very rare surname, and France. Likewise, Cosny is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Cosny | Singapore, Democratic Republic of the Congo, France, Nigeria, Myanmar |