Cognomen Dayon-Ay (Dayon-Ay 
) , around the world, is an extremely rare family name. The last name Dayon-Ay is characteristic of South-eastern Asia, particularly Philippines, where it is an extremely rare surname. Parts of the name also exists independently as a last name Dayon, and a last name Ay.
| VARIANT | COUNTRY |
|---|---|
| Dayon-Ay | Philippines |