Cognomen Cilay (Cilay 
) , throughout the world, is a rare last name. The cognomen Cilay is habitual in Turkey, where it is a very rare surname, Indonesia, and India, where it is an extremely rare surname. Likewise, Cilay is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Cilay | India, Indonesia, Mexico, Turkey, Brazil |