(Spanish) form of Carmel, altered by folk etymology to the form of the Latin word carmen ‘song’. It is now sometimes found as a given name in the English-speaking world, in spite of, or perhaps because of, its association with the tragic romantic heroine of Bizet's opera Carmen (1875), based on a short story by Prosper Mérimée.
Spanish and Portuguese: 1. from a personal name, byname, or nickname, dos Santos (from Spanish Todos los Santos ‘All Saints’, Portuguese Todos os santos), typically bestowed on a child born on All Saints’ Day. 2. in many cases, a habitational name from any of the places named Santos, from the dedication of a local church or shrine to all the saints. This is a very common Portuguese surname.