1770+ Boy Names Ending in O

All names Cas are cool right night, from Cassius to Cassian to Caspian to, yes, Casimir and its Latin form Casimiro. An attractive possibility in this appealing group.

A charming -o name with cool nickname possibilities, Ramiro is also a historical choice: there were 2 Aragonese Spanish kings named Ramiro.

Popular among Hispanic parents, it explains the source of the nickname Gonzo.

A very popular Japanese boys' name whose characters refer to the constellation Ursa Major. Short form Hiro might work better in the West, as may another popular Japanese boys' name, Ren.

Has a lively and swaggering sound, and also some unfortunate associations with Reno, city of gambling and failed marriages.

In Italy, a common melding of two popular names, heard in the US as well.

The European-sounding name of the husband of Little House on the Prairie author Laura Ingalls Wilder actually arose as an Anglicisation of an Arabic name: "Way back in the time of the crusades there was a Wilder…and an Arab…saved his life. El Manzoor was his name." Almanzo James Wilder was affectionately called "Manly" by his family.

Cute Finnish version of Michael.

Fiery sound and uplifting meaning, but it's also among the Top 100 dog names. Spelled Fiyero, it's the hero of the book and musical "Wicked."

A Japanese name with a great meaning, a cool Kai sound, and lots of potential to become an international export.

Rarely, if ever, heard outside the Jewish community.

If Portia can become Porsche, then Apollo can morph into Polo -- the imprint of designer Ralph Lauren.

Variation of the popular religious name, boosted by megastar Portuguese footballer Cristiano Ronaldo.

Its jaunty o-ending makes this name more appealing than most of its Germanic brothers, and we hope we're beyond the constant response to his name being "Where's Waldo?" The weighty reputation of writer and philosopher Ralph Waldo Emerson adds a measure of backbone to the name.

Intriguing twist on Jacob, but may be too strongly associated with Michael Jackson.

Protagonist of the manga and anime series Demon Slayer: Kimetsu no Yaiba. The kanji used to spell his name give it the meaning of "coal + calm son," which describe his former profession as a coal worker.

Italian heritage name. It's sweet and simple, but has fallen almost out of use since its heyday in the 1960s.