Cognomen Thythavy (Thythavy 
) , worldwide, is a rare family name. The surname Thythavy is habitual in South-eastern Asia, particularly Laos, where it is quite a rare surname, and Thailand, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Thythavy | Laos, Thailand |
Vithida, and Siphachanh