What Guillermo means
Guillermo is a boy name of Germanic origin meaning "resolute protector". It is built from Germanic wil (will, desire) and helm (helmet, protection). It is pronounced gee-YER-mo.
Guillermo del Toro, Oscar-winning director from Guadalajara. Guillermo Prieto, poet and finance minister.
Nicknames in Mexico: Memo. Memo repeats the stressed syllable of Guillermo (-mo) in the doubled pattern typical of Spanish child speech. See the guide to Mexican nicknames.
Popularity: one of the most common names in Mexico. See the current top names.
