Guillermo
/G-AH-IH-L-L-EH-R-M-AA/
Resolute protector, the Spanish form of William, from Germanic wil (will, resolve) joined to helm (helmet, protection). It names a guardian whose protecting strength is matched by an unbending will, and stands as the enduring Iberian form of that great medieval name.
See Guillermo scored for your familyMeaning & origin
Guillermo is a boy's name of Spanish origin, traditionally used in Christian families. The name means "Resolute protector, the Spanish form of William, from Germanic wil (will, resolve) joined to helm (helmet, protection). It names a guardian whose protecting strength is matched by an unbending will, and stands as the enduring Iberian form of that great medieval name." and belongs to the Courage cluster — names for children who will grow into bold, fearless hearts.
Beyond its Christian heritage, Guillermo is also used in Atheist traditions, reflecting how this name has traveled across cultures.
Common among Spanish, European, Latino, Mexican, Cuban, Argentine, Colombian, Chilean, Peruvian, Venezuelan, PuertoRican, Dominican families, Guillermo carries cultural weight that goes beyond its dictionary definition — it's a name with a story and a community.
Numerology of Guillermo
Numerology assigns each name a single-digit destiny number by summing its letter values. Different schools use different mappings — NameRoot computes both so you can see how Guillermo resonates in either tradition.
How Guillermo sounds
NameRoot scores the phonetic fit of every name against the sound of your last name. The pronunciation of Guillermo breaks down into 9 phonemes: /G-AH-IH-L-L-EH-R-M-AA/. In the app, you'll see how those sounds flow with your family name across rhythm, stress, and consonant clusters.
Nicknames
Common affectionate forms of Guillermo — useful for everyday family conversation, early childhood, or as standalone given names themselves.
The six signals, applied to Guillermo
NameRoot scores every name across six independent dimensions. Here's how Guillermo maps to each — install the app to see the full compatibility score for your specific family.
Names similar to Guillermo
If Guillermo resonates with you, these names live in the same world — drawn from the same tradition, sharing the same meaning, or echoing a similar sound.
From the same tradition
Other Christian boy names, common in Spanish families
Sharing the same meaning
Other Christian boy names from the Courage cluster
Names that sound similar
Christian boy names that open with the same syllables as Guillermo
Common questions about Guillermo
What does the name Guillermo mean?
Guillermo means "Resolute protector, the Spanish form of William, from Germanic wil (will, resolve) joined to helm (helmet, protection). It names a guardian whose protecting strength is matched by an unbending will, and stands as the enduring Iberian form of that great medieval name.." It is a boy name of Spanish origin, traditionally used in Christian families.
Is Guillermo a boy or girl name?
Guillermo is most commonly used as a boy name.
What is the origin of the name Guillermo?
Guillermo is of Spanish origin, used in Christian, Atheist traditions, commonly among Spanish, European, Latino families.
What are common nicknames for Guillermo?
Common short forms of Guillermo include Guili, Guil.
What is the numerology of Guillermo?
Guillermo has a Pythagorean destiny number of 4 — stability and disciplined work.
See how Guillermo scores for your family
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