In all the world, สายยงค์ (สายยงค์ 
) is a very rare epicene first name. The given name สายยงค์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare gender-neutral name. Also, สายยงค์ is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| สายยงค์ | Thailand |