Best Boy Names Ending in O
The best boy names ending in O include selections from those top names as well as unique O-ending names. The Top O-ending boy name in the US right now is the Spanish Mateo. Along with Mateo, other boy names ending in O in the US Top 500 include Leo, Santiago, Milo, and Theo.
Unique boy names ending in O that make our best list include Anselmo, Benno, Caio, and Laszlo. Of course, O is the usual ending for boys' names in Italy, Spain, and other Latinate countries. O-ending boys' names popular internationally include choices from those lands as well as boys' names with other origins that carry the O ending. We've included a few fashionable names here that don't technically end in O but in the O sound. The list is ordered by current popularity on Nameberry.
RELATED:
- 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.
 - Roscoe
Origin:
NorseMeaning:
"deer forest"Description:
Fairly popular a hundred years ago but out of sight now, the quirky Roscoe deserves a place on every adventurous baby-namer's long list. It joins Rufus, Roman, Remy, Romulus, and Ray as one of the R names that sound fresh again after too many years of Robert, Richard, and Ronald.
 - 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.
 - 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.
 - 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.
 - 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.
 - 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.
 - 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.
 - 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.
 - 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.
 - 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.
 - 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.
 - Beau
Origin:
FrenchMeaning:
"handsome"Description:
Beau suggests someone devilishly handsome, with a large measure of southern charm—a nice image to bestow on your boy. Often solely a nickname in the past, it's now standing firmly on its own. Beau has been on the Social Security list non-stop since 1969.
 - 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.
 - Lorenzo
Origin:
Italian; Spanish, variation of LaurenceMeaning:
"from Laurentium"Description:
Latinizing Lawrence gives it a whole new lease on life. Like Leonardo, Lorenzo has been integrated into the American stockpot of names, partly via actor Lorenzo Lamas. Other associations are with Lorenzo de' Medici, the Florentine Renaissance merchant prince and art patron, Renaissance artists Ghiberti and Lotto, and the upstanding young man who married Shylock's daughter Jessica in Shakespeare's The Merchant of Venice.
 - 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.
 - Emilio
Origin:
Spanish and Italian variation of EmilMeaning:
"rival"Description:
Dashing and suave, with a hint of poetry and gentleness, Emilio is an appealing and international choice. A solid favorite in Italy, it is also on the rise in the US, France, Austria, and the UK.
 - Leandro
Origin:
Spanish, Portuguese, and Italian variation of LeanderMeaning:
"lion-man"Description:
Leandro is a variation of the Ancient Greek name Leander, created by combining the Latin words leo and Andro together, to get a meaning that suggests strength, power, and bravery. The Hero and Leander myth lends the name a romantic, poetical feel, while it's association to Bishop Leander of Seville gives it a more saintly quality.
 - 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.
 - Viggo
Origin:
ScandinavianMeaning:
"war"Description:
Though to most Americans Viggo is a one-person name attached to intense actor Mortensen, it is actually an old Norse name dating back to the Vikings, and is currently the 32nd most popular appellation in Sweden. Viggo Mortensen is a Jr., sharing his name with his Danish father.
 

