Surname Sinkhunathan (Sinkhunathan 
) , around the world, is a very rare family name. The cognomen Sinkhunathan is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Sinkhunathan | Thailand |
Waree, Paphon, Ananwat, Wattaphat, and Watthaphat