Cognomen Gammi (Gammi 
, Gamme 
) , across the world, is quite a rare last name. The cognomen Gammi is characteristic of Norway, where it is quite a rare surname, Belgium, where it is a rare surname, and Sweden. Not in comparison with a country's population, the name is most common in India, Norway, and Belgium. Likewise, Gammi is the forename as well as the last name.