Cognomen Watson-Trotter (Watson-Trotter 
) , in all the world, is an extremely rare last name. The family name Watson-Trotter 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 Watson, and a last name Trotter.
| VARIANT | COUNTRY |
|---|---|
| Watson-Trotter | United States |