Throughout the world, Gadaj (Gadaj 
, Гадай 
) is an extremely rare mostly boy's, but uncommonly female forename. Likewise, Gadaj is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Gadaj | Germany, United States, Poland, India |
| Гадай | Kazakhstan, Russia, Kyrgyzstan, Ukraine |