Cognomen Dequay (Dequay 
) , throughout the world, is a very rare last name. The last name Dequay is characteristic of France, where it is a very rare surname, the United Kingdom, where it is an extremely rare surname, and the United States. Much less frequently, Dequay is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Dequay | United Kingdom, New Zealand, United States, France |