Names Ending in O for Boys

As classic as it comes in Italy — Filippo was once common during the Renaissance, and today remains in the Top 25.  

Filippo

Ido is a multicultural name seldom heard in modern America but popular in the Middle East. As transliterations, Ido and its other form Iddo are equally correct.

The Biblical Ido was a minor prophet of the Old Testament who lived in the time of Solomon.

This West African name has an upbeat, energetic sound, yet it is traditionally used for a son who was born during troubled times.

Iniko

Jamario is a distinctive masculine name likely formed as a creative blend of the popular name Jamar (of Arabic origin meaning 'handsome') and the common Latin suffix '-io.' Alternatively, it could combine elements of James (Hebrew, meaning 'supplanter') with Mario (Latin, meaning 'warlike'). 

This melodic, four-syllable name emerged during the 1970s and 1980s, reflecting the trend toward distinctive, musical-sounding names with cultural resonance. While uncommon in the general population, Jamario has maintained consistent though limited usage over recent decades. The name has a rhythmic quality and contemporary feel that balances uniqueness with pronounceability. Its distinctive character reflects cultural naming innovations while maintaining connections to more traditional name elements.

Jamario

Keno is a masculine name with multiple cultural origins. In Native American Hopi tradition, it means 'three,' while in some African cultures, particularly Nigerian, it can mean 'gift' or 'blessed child.' The name also has Japanese connections where it can mean 'happy one.' Keno remains relatively uncommon as a given name in most Western countries but has gained some recognition through its association with the lottery-style gambling game of the same name, which originated in China. The name's brevity and strong 'o' ending give it a contemporary feel despite its traditional roots. Keno appeals to parents seeking a unique, multicultural name with positive connotations.

Keno

Kosmo is easy to spell, pronounce, and understand, yet most English speakers would spell this uncommon name Cosmo.

Kosmo

A spirited Japanese name with a strong but cosy feeling meaning, Minato is popular in its native Japan.

Minato

An endearing Spanish and Portuguese form of Paul.

Paulino

Short, snappy, and stylish, Reo may be viewed in a number of ways:. It could be an alternative spelling of Spanish Rio or the Greek Rhoeo, both associated with rivers and flowing water. Alternatively, it could be a Japanese name, used as a variation of Leo, or a a name in its own right, meaning "graceful + cherry blossom",, "graceful + sun", "beautiful + flourishing", and "actor, musician + flourishing".
 
In terms of pronunciation, it would be REE-o in English, as reh-o if used as a form of Rhoeo, and as REH-O in Japanese.

A number related name option, Sixto is the Spanish variation of the Latin Sixtus, which means "sixth", or "scraped", depending on what root you follow. It sounds better when said the Spanish way (seeks-to) rather than as an English speakers might read it intuitively. 
 
A notable bearers was musician Sixto Rodriguez, better known by just his surname.

Sixto

Taeo

Yeiko

Zaqueo

Attractive name from the Old Testament. Adino was one of David's "mighty men," though texts do disagree on his name.

Adino

Dazzling Japanese name featured in the 2021 reboot of Gossip Girl as the given name of Aki Menzies.

Akeno

A saint who is especially popular in Galicia and Asturias in Spain, who is said to have sailed across the Atlantic to paradise. His name may derive from Germanic Adelmar, possibly influenced by Latin amarus "bitter".

Amaro

Playful but with plenty of substance, Bartolo is an Italian short form of the grand Bartholomew which could lead you to further nicknames Bo and Tolly. Also used in Spanish, a notable bearer is Bartolo Longo, a former Satanist priest who returned to Catholicism and dedicated his life to his faith and charity. He was canonized as a saint in 2025 by Pope Leo XIV, which could renew interest in the new. 

Bartolo

Candelario

When Kim Kardashian and Kanye West named their daughter Chicago — after West's hometown — we expected it to rise for baby girls. But American parents have taken to Chicago as a boy name. It's been given to more boys than girls every year since 2018.
 
The city's name was derived from the Algonquin word shikaakwa, meaning "wild garlic". Onions, ramps, and garlic once grew in the area. The French transliterated shikaakwa to "Checagou" or "Chicagou", from which we get Chicago today.

Chicago

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.

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.

Baby boy Names ending in the letter O, with meanings, origins, and popularity, including top boy names that end in O such as Milo and Kylo along with unique O-ending names such as Quinto. (Page 23)

1770+ Boy Names Ending in O