US Popularity Rank: 1732

Origin: Mexican

Meaning: Will helmet

Guillermo is a baby boy name of Mexican and Spanish origin, meaning “will helmet.” This name is no doubt a great fit if you already sense a mini conqueror coming your way. But if your little Guillermo is more of the gentle-natured sort, this name can also be a celebration of their heritage. Originally known as the Spanish version of William, this name could tie in baby’s German heritage, too. But regardless, little Guillermo could become a resolute protector of anything and anyone they love with such a rich background to lean on.