Word-O Name

Bean: His name is Elfo for Pete's Sake.
Sorcerio: Tacking an "O" on the end of "Elf"? Bah!

— Disenchantment, "To Thine Own Elf Be True"

Need a code name? If you're a man, just pick a word appropriate to your abilities or temperament, add "O" to the end (or replace the end if that sounds better), and you're ready to go! For women, use the same tactic, but with an "A" instead.

This naming convention shows up a lot among superheroes and villains, but can show up elsewhere as well.

Note that the rest of the character's name must be a significant word or variant of such. Rambo's name might end in O, but he is not an example of this trope. Same for Luna.

Subtrope of Meaningful Name. Compare El Spanish "-o" and Ladyella. These names are highly prone to Lazily Gender-Flipped Name or Sobriquet Sex Switch where the character's O is simply changed to an A, or vice versa. Compare Thing-O-Matic, which is a similar naming scheme for gadgets.

---

Examples:

Comic Books

• DC Comics has such characters as Amazo, Bizarro, Chemo, Computo, Despero, Eclipso, Giganta, Volcana, Prince Evillo, Mano, Metallo, Metamorpho, Sinestro, Starro, Titano, and Universo. Lampshaded in a Justice League of America Annual backup story, in which Starro assembles the O-Squad.
  Starro: We villainous few share two common bonds — The burning desire to enslave the Earth over the charred remains of the hated Justice League...
  ...and our names all end in "O".
• Marvel Comics has Aiero, Professor X's machine Cerebro, Chemistro, Electro, another Elektro (a giant robot), Magneto^note Though while it fits the trope ("Magnet" + "O"), it is actually an existing word as well, Mentallo, Mysterio, Obnoxio the Clown, and Pyro (although that is a recognised word element).
• There was a villain on The Tick named Destroyo (real name Leonid Kasparov Destroyovitch).
• Tigra, a female hero with powers based on a tiger. There's also Thundra, who doesn't actually have thunder powers but it does create the right impression for her.
• Early Golden Age Wonder Woman had several villains and allies whose names were created by taking an existing word and tacking on an -a, regardless of gender. These included, among others, Athleta, Glamora, Inventa, Jumpa, Mammotha, Metala, Signa, and Wanta.

Comic Strips

• Garfield:
  • One comic, a small animal calls Gafield "The Amazing Lardo" to tease him, implying that he's astoundingly fat.
  • In one story arc, Garfield and Odie join Binky the Clown's circus. Binky introduces Garfield as "Rotundo the clown" to the audience during a performance (to Garfield's chagrin since it's obviously a jab at him being fat).

Films — Animation

• Overlaps with As Long as It Sounds Foreign in The Adventures of Captain Wrongel: two villains are called Giuliko Banditto ("zhulik" meaning "conman" in Russian) and de la Voro Gangsteritto ("vor" meaning "thief").

Films — Live-Action

• Dr. Roger Fleming, the secondary antagonist of The Lost Skeleton of Cadavra, names the woman he creates from forest creatures "Animala".

Literature

• In Death series: The books Survivor in Death and Innocent in Death have little kids putting "o" at the end of words. This creates words like "crap-o", "what-o", and "lame-o". The implication is that kids do this to sound impressive.

Live-Action TV

• Breaking Bad: When Jane and Jesse start dating, one scene shows her looking over superhero sketches he made in high school; he's particularly proud of one character he named Backwardo, then Rewindo ("His power is he moves backwards.")
• Electra Woman and Dyna Girl (Electric and Dynamic) are a Gender Flipped Batman and Robin expy, originally made as part of The Krofft Supershow. They fight crime with gadgets developed by altruistic inventor Frank Heflin.
• Lidsville:
  • The magician at the amusement park seen in the show's intro is named Merlo, obviously as a nod to Merlin.
  • When Mark poses as a rival magician to humble Hoodoo, he goes by the name Whizzo.

Music

• The Styx song Mr. Roboto features a group of robots known as robotos.

Theatre

• The Marx Brothers consisted of Groucho, Harpo, Chico, and Zeppo^note  and their non-famous brother Gummo., with each brother's nickname corresponding to their personality. E.g. Harpo played the harp, Chico (pronounced Chick-o) was a ladies' man, and Groucho was known for his surly personality. Supposedly this sort of nickname was trendy in the 1910s when the brothers got their start in Vaudeville.

Video Games

• Bayonetta: There's of course the main protagonist, Bayonetta.

Web Animation

• The Pink City: Invisible-O the ghost, whose primary trait is that she's invisible.

Web Videos

• The Spoony Experiment has Dr. Insano, a Mad Scientist.
• Helluva Boss: Blitzo insists the "o" is silent and his name is just pronounced like "blitz", but one of his former colleagues pronounces and emphasizes the o, implying that he changed it at some point.

Western Animation

• Animaniacs: The Warner Brothers are named in the same style as The Marx Brothers, with Yakko the talker and Wakko the oddball. The Warner Sister, however, just goes by Dot.
• Amphibia: In Season 2, Polly befriends a frog robot, which she names Frobo.
• Chip 'n Dale: Rescue Rangers:
  • The deaf-mute, nameless Harpo Marx look-alike mouse in the episode "The Pied Piper Power Play".
  • In "It's a Bird, It's Insane, It's Dale!" when Dale gets Rubber Man powers and decides to be a superhero, he dubs himself Rubber Bando, and sallies forth to fight evil and thwart villains.
• Disenchantment: A Running Gag involves most of the Elves being named in this manner, with the word the "O" is added to either reflecting their personality, appearance, or place in the Elf Society. There's Elfo, Rulo (the king), Leavo, Returno, Annoyo, Desserto and Speako, just to name a few. Elfo's name is an Ironic Name since it's revealed near the end of Season 1 that he is only half-Elf. The female Elves avert the "A"-names however; the only named one so far is named Kissy. Season 4 reveals the Trogs, a race of small underground dwelling creatures, are also named in this manner which foreshadows the fact that Trogs and Elves are in fact the same race.
• Futurama:
  • Bender's doppelgänger is another bending unit named Flexo (since his function, like Bender, is to bend girders).
  • The Big Bad of the episode "The Inhuman Torch" is an evil flame creature appropriately named Flamo.
  • Bender gets an idea for a name like this in "Less Than Hero":
    Fry: (discovering they're all out of the ointment that gave him and Leela superpowers): El zilcho!
    Bender: (intrigued) Hmm, "El Zilcho." Hey, is it too late to change my superhero name?
• Freakazoid! villain Invisibo, who got the name from Freakazoid because it sounded better than his real name, Amon Kor-Unch.
• G.I. Joe has the villain Destro.
• Codename: Kids Next Door: The villain for a Show Within the Show based off the KND is called Homework-O, an evil robot who keeps kids from doing their homework.
• Lilo & Stitch: The Series: One of Stitch's cousins, Experiment 345, is found by a circus and given the name Elastico due to his rubbery body.
• Mixels has a few examples, such as Slusho, Busto, Splasho, and Screeno.
• Rocko's Modern Life: While most of the puns involving names in O-Town place the "O" in the center, the chief company in the city is called Conglom-O.
• She-Ra and the Princesses of Power: The princess of Plumeria, who has the ability to grow plant life at will, is named Perfuma, after the pleasant scent of flowers. The show also has Frosta, the Princess of the Kingdom of Snows, and Glimmer's aunt, the sorceress Castaspella. This was also the case in the shows predecessor, She-Ra: Princess of Power.
• South Park: In ''AWESOM-O", Cartman disguises himself as a robot named AWESOM-O to fool Butters.
• Teamo Supremo: The 3 main heroes use this naming convention for their team name. Averted with their individual superhero names.
• ThunderCats (1985): has main protagonist Lion-O, who is appropriately enough a lion. The show has quite some other characters whose names reflect their species: Panthro and Cheetara, and minor characters like Lynx-O, Pumyra, Jagara, Panthera, Sauro, and Spidera.
• The Weekenders: In the episode where Tino tries to overcome his fear of clowns, he attends a clown school. The first thing he has to do is tell the teacher his clown name when asked. When the teacher points at Tino...
  Tino: Aah! [falls off his seat]
  Teacher: Uuuuh, [writes name on chalkboard] Screamo.
• Wild Kratts: Many of the names that Martin gives animals are simply the name of the species with an "-a" on the end, such as "Crocodilla".
• Zig & Sharko: The latter half of the titular characters is a shark named Sharko.

---