Cognomen ซินไทย (Cynthai 
, ซินไทย , Zinthai ) , in the entire world, is a very rare surname. The cognomen ซินไทย is habitual in Thailand, where it is a very rare surname, and Nigeria. Likewise, ซินไทย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Cynthai | Thailand, Nigeria, United States, India, France |
| ซินไทย, Zinthai | Thailand |