Family name Giedd-Lyon (Giedd-Lyon 
) , throughout the world, is an extremely rare last name. The family name Giedd-Lyon is characteristic of Northern America, particularly the United States, where it is an extremely rare surname. Parts of the name also exists independently as a last name Giedd, and a last name Lyon.
| VARIANT | COUNTRY |
|---|---|
| Giedd-Lyon | United States |