1770+ Boy Names Ending in O
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Boy names ending in O offer many intriguing options, from such top names as Theo to unique O-ending names from Kylo to Zino.
Mateo is the most popular boy name ending with O right now, though there are nearly 100 O-ending boy names among the US Top 1000. Along with Mateo, other boy names in the US Top 1000 include Leo, Santiago, Diego, Romeo, and Antonio.
And there are hundreds more unique names for boys that end with the letter O worthy of your consideration. These range from the biblical Jethro to the ancient Greek Cosmo to the cool, modern Rio and Po.
Here are all Nameberry’s boy names that end with the letter O, ordered by their current popularity on Nameberry.
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- Milo
Origin:
Latin and Old GermanMeaning:
"soldier or merciful"Description:
Milo is most commonly considered to be Germanic name derived from the Latin word miles, meaning "soldier." However, there is evidence to suggest it also may have independently spawned from the Slavic root milu, meaning "merciful." Milo predates brother name Miles, a variation that evolved when the name immigrated to the British Isles in the Middle Ages. Mylo is an alternate spelling.
- Mateo
Origin:
SpanishMeaning:
"gift of God"Description:
Mateo is a Latinate name that like Mia and Luca, is becoming popular far beyond its native Spanish community. With its fresh feel and charm, it made a surprise entrance to the boys' Top 10 in 2023.
- Arlo
Origin:
Irish or EnglishMeaning:
"between two hills"Description:
Quirky cool Arlo is now well and truly back. Last year it broke into the US Top 200 boy names and consistently ranks among the most popular boy names on Nameberry. Along with its Irish and English roots, Arlo may be a shortened form of the Italian Carlo or the Spanish Carlos, both forms of Charles,and in Basque-speaking regions it is the word for area.
- Hugo
Origin:
Latinized form of HughMeaning:
"mind, intellect"Description:
Hugo, the Latin form of Hugh, has more heft and energy than the original -- and of course we love names that end (or begin, for that matter) with an o. This one is especially appealing because it's backed up by lots of solid history and European style.
- Otto
Origin:
GermanMeaning:
"wealthy"Description:
Otto is cool again. Long a quintessential Old Man Name, Otto has been promoted to trending darling of adventurous baby namers.
- Elio
Origin:
Italian, SpanishMeaning:
"sun"Description:
Elio is a sunny and spirited Italian and Spanish name that makes a great crossover prospect, which could catch on as Enzo has. Elio is also currently popular in France, ranking in the Top 250.
- Enzo
Origin:
Italian variation of Henry, GermanMeaning:
"estate ruler"Description:
You may be surprised to know that Enzo is now a Top 100 boy name in the US and the UK, where it has been climbing straight uphill since the turn of this century.
- Leo
Origin:
LatinMeaning:
"lion"Description:
Leo is a strong-yet-friendly name that was common among the Romans, used for fourteen popes, and is now at its highest point ever in the US thanks in part to Leonardo "Leo" DiCaprio.
- Theo
Origin:
Diminutive of TheodoreMeaning:
"gift of God"Description:
See the popularity graph below for the name Theo? It's been heading straight uphill since 2010, when it hopped back onto the Top 1000 after a 60+ year absence.
- Cosmo
Origin:
Italian, English, GreekMeaning:
"order, beauty, universe"Description:
With a touch of celestial power, a hint of clunky charm, and the totally cool -o ending, Cosmo may well be finally shaking itself free of both the Seinfeld association (which made it a punchline of a joke) and the cartoon fairy association from The Fairly OddParents. In fact, it is in the Top 1000 in the UK and a favorite on Nameberry.
- Nico
Origin:
Italian diminutive of Nicholas, GreekMeaning:
"people of victory"Description:
Nico is one of the great nickname names, full of charm, energy and effortless cool -- a neo Nick.
- Ivo
Origin:
Germanic, SlavicMeaning:
"yew wood, archer; God is gracious"Description:
Succinct, stylish, and catchy, Ivo has the energetic impact of other names ending in -o. It is a multicultural choice with two distinct origins, and, as such, is familiar across a variety of countries, ranging from the Netherlands to Brazil, from Portugal to Czechia.
- Apollo
Origin:
Greek mythology nameMeaning:
"destroyer; strength; father's light"Description:
With mythological names rising, the handsome son of Zeus and god of medicine, music, and poetry among many other things might offer an interesting, and melodic option. Similar in style to Atlas and Atticus and similar in sound to Arlo, Paolo, Paul, and Ollie, Apollo entered the US Top 1000 back in 2012, and was propelled upwards after it was chosen by Gwen Stefani and Gavin Rossdale in 2014.
- Rio
Origin:
Spanish, Portuguese, JapaneseMeaning:
"river; place of the cherry blossoms"Description:
Rio is a reductive ranchero place-name with an attractive Tex-Mex lilt. No Doubt's Tom Dumont has a son named Rio Atticus.
- Matteo
Origin:
ItalianMeaning:
"gift of God"Description:
This attractively energetic Italian version of the classic Matthew is primed to move further and further into mainstream American nomenclature. Mateo is technically the Spanish version, but many parents in the US use the two spellings interchangeably.
- Cato
Origin:
LatinMeaning:
"all-knowing"Description:
Cato conjures up images of ancient Roman statesmen and southern antebellum retainers; it could have revival potential, with its 'O' ending and the current interest in the names of Greek and Roman antiquity.
- Runo
Origin:
FinnishMeaning:
"poem"Description:
An appealing Finnish name, with a touch of literary magic and whimsy, Runo means "poem" in its native language. Traditionally said with a slightly rolled R and a softer 'oh' sound at the end (more like in on that in open), it comes from the Proto-Norse and Proto-Germanic, where it means "secret, literature, letter", in turn relating it to rune.
- Santiago
Origin:
Place-name or LatinMeaning:
"Saint James"Description:
Santiago is a spirited Spanish name with great crossover potential. It's a place-name (a city in Chile), a surname, and the name of the patron saint of Spain.
- Bruno
Origin:
GermanicMeaning:
"brown"Description:
Tough-yet-cuddly Bruno is an international name even in its origins: it derives from the Germanic word for "brown" plus a Latin ending, and was borrowed as a color word in many European languages.
- Diego
Origin:
Spanish variation of JamesMeaning:
"supplanter"Description:
The energetic Diego is rising rapidly along with a lot of other authentically Spanish baby names that work perfectly well with surnames of any origin.
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