What does the name Guillermo mean? The meaning of the name Guillermo is Strong-willed Warrior. The origin of the name Guillermo is Spanish. This is the culture in which the name originated, or in the case of a word, the language.
People who like the name Guillermo also like: Liam
, Oliver Graciela
Name Notes: A form of William. Pronounced "gee-YEHR-mo" with a hard G.