Boy Name · Germanic Origin
Guillermo
Guillermo — a boy name from the Germanic tradition — is an uncommon, standout choice. Its meaning, "Resolute protector", anchors the name in something deeper than sound alone. If Gillermo is on your shortlist, Guillermo belongs in the same conversation.
Guillermo meaning, origin, and usage
Meaning: Resolute protector
Origin: Germanic naming roots help connect Guillermo to related Germanic baby names.
Pronunciation: Baby Name Studio pronounces Guillermo as G·U·I·L·L·E·R·M·O, with 9 letters and a boy usage profile.
Popularity: According to Baby Name Studio's 2026 tracker, Guillermo is an uncommon, standout choice in the Rare tier.
Guillermo variants, nicknames, middle names, and sibling names
- Variants and spelling ideas: Guillermoa, Guillermoe, Guillermoy, Guillerm.
- Nicknames: Guill and G.
- Middle names: Pair Guillermo with a middle name that balances its substantial sound; start with the Guillermo middle name generator.
- Sibling names: Gillermo, Guillermina, Geronimo, Gaylord, Guilford — full picks on the sibling names for Guillermo guide for a cohesive sibset.
- Similar names: Looking for names that sound like Guillermo? Browse our names like Guillermo guide for phonetic-neighbor picks.
- Explore more: use the Baby Name Explorer, name search, AI name generator, and Baby Name Studio homepage.
Frequently asked about Guillermo
What does the name Guillermo mean?
Guillermo means "Resolute protector" and is of Germanic origin.
What is the origin of Guillermo?
Guillermo originates in Germanic naming tradition.
How do you pronounce Guillermo?
Guillermo has 9 letters and is most commonly stressed on the first syllable.
Is Guillermo a boy's or girl's name?
Guillermo is primarily used as a boy's name in US records.
How popular is Guillermo in 2026?
In our 2026 popularity tracker, Guillermo sits in the Rare tier — an uncommon, standout choice.
What names are similar to Guillermo?
Names that share Guillermo's sound and style include Gillermo, Guillermina, Geronimo, Gaylord, Guilford.
What middle names pair well with Guillermo?
Good middle-name fits for Guillermo pair an opposite syllable rhythm: if Guillermo is short, lean longer (e.g. classical or three-syllable middles); if Guillermo is longer, a one-syllable middle keeps the full name from feeling heavy.
What are good sibling names for Guillermo?
Sibling names that pair naturally with Guillermo share its rhythm without rhyming — Gillermo, Guillermina, Geronimo all sit comfortably alongside it on a shortlist.