Cognomen Thaddy (Thaddy 
) , all around the world, is a rare surname. The last name Thaddy is habitual in the Democratic Republic of the Congo, where it is a rare surname, Nigeria, where it is a very rare surname, and the United States, where it is an extremely rare surname. Very seldom, Thaddy is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thaddy | Philippines, Democratic Republic of the Congo, Germany, United States, Nigeria |