Verbal Tic Name

""All she can say is 'Nyu', so let's call her that.""

- Kouta, Elfen Lied

In Pokémon-Speak, the only thing a character says is his or her name. This is essentially the inverse: a character is named for the only thing he or she says. Sometimes the latter causes the former.

The way it usually works is someone with a limited or one-word vocabulary is named after that one word. Often, this will occur because other characters don't know this character's real name (if there even is one), and are uncomfortable with not having something to call them beyond "Hey, you." The simple solution: Take the only word(s) they ever utter and turn that into their name.

Note that, despite the title, the source of the name isn't necessarily a Verbal Tic. However, the spirit is there in that the character's limited vocabulary is his or her defining attribute.

Anime & Manga

 * Chi from Chobits.
 * Chomesuke from D.Gray-man, cho~! Also, Lero/Relo.
 * It's suggested from the director's notes that Culumon (Calumon in the dub) from Digimon Tamers, not being a real Digimon at first, gave himself his name and adopted a Verbal Tic from it.
 * Giru in Dragon Ball GT
 * Nyu from Elfen Lied.
 * Chibi-Chibi from Sailor Moon
 * Pyoro in Vandread.
 * The little draconic creature Raac in Warcraft: The Sunwell Trilogy.
 * Nyorori from 12 Senshi Bakuretsu Etoranger ends every sentence with his name, Nyorori.
 * Di Gi Charat's Pyokola Analogue III ends hers with "pyo!"
 * Mone in Yumeria.

Comics

 * Todd Casil from Johnny the Homicidal Maniac and the Spin-Off Squee! makes a squeaking noise when he's scared, which is quite often. When he meets the Ax Crazy Johnny and is asked his name, naturally the only noise he could muster up was "Squee!", which later became Johnny's nickname for him.

Film
"Henry Hill: [narrating] ...And Jimmy Two-Times, who got that nickname because he said everything twice, like: Jimmy Two-Times: I'm gonna go get the papers, get the papers."
 * Eegah in the film of the same name.
 * Yeah-Yeah from The Sandlot.
 * In Topsy Turvy, Gilbert dubs a young Japanese woman "Miss Sixpence Please" after the only two words of English she seems to know.
 * Goodfellas:

Literature

 * Errand from The Belgariad. His real name, given in the Mallorean, is Eriond.
 * Oy from the Dark Tower series. He's a billy-bumbler, which is a talking raccoon-like creature native to Mid-World. The name comes from his attempts to say "boy".
 * Gleep the baby dragon in the Myth Adventures book series. Subverted in a story written from Gleep's POV, where it's shown that he's quite intelligent and erudite—the problem isn't his linguistic ability, it's that his vocal cords aren't yet capable of human speech.
 * He does learn to talk more understandably in later books, however.
 * Gollum from Lord of the Rings, because of the noise he made in his throat, and Niniel (meaning "tear-maiden") in The Silmarillion, after losing her memory.
 * A Song of Ice and Fire has Hodor, the lovable simpleton stable boy. His only word is "Hodor". People assumed that that is his name, but it's revealed that his real name is Walder, but since he only said Holdor, that's what everyone calls him.
 * A partial example from Discworld is Hodgesaargh the falconer from the kingdom of Lancre. He speaks normally, but that's what he says whenever asked for his name (thanks to one of his overzealous falcons trying to attack him): "I'm Hodges... aargh!".
 * Also, from The Wee Free Men is Sneebs, so called because that's all he says, though whenever he says "Sneebs" you hear words in your head.
 * As a half-example, in the Legends of Ulm series, the protagonist, Gom, was named for the sound he made as a baby.
 * In The Edge Chronicles, Twig is named his own name by a trog insistent on keeping him as a pet. Her mother insists that she won't have a pet that talks, and when Twig unthinkingly answers her question "What's your name?", he tries to make it sound like a verbal tic: "Twigtwigtwigtwig. Twigtwigtwig". The trog delightedly responds "I think I'll call him Twig."
 * In the Layer Cake novel, the Diabolical Mastermind's bodyguard gained a habit from his SAS experience of calling everyone "Troop". Thus, he's identified as Mr. Troop (in the film, he doesn't have the habit, but is still given that name).
 * The World According To Garp, inverted. Technical Sergeant Garp's name is the only thing he can say.
 * Redwall: "Assssmodeussssss ..."
 * In the Narnia novel The Magician's Nephew, when the Talking Beasts adopt Uncle Andrew as a pet they name him Brandy because he makes that noise so often. Unusual in that Uncle Andrew was perfectly capable of speech. The animals named him this because they couldn't understand much of the other stuff he was saying—partly because he was rendered rather incoherent by the previous events of the novel, and partly because he shut off his mind from communication.
 * Bubbles from Finding Nemo got his name from the fact that he is constantly obsessed with an aquarium decoration that spews bubbles.
 * Freak the griffin from The Kane Chronicles is partly named because of his freakish behavior, and partly because of the screeching noise that he makes.

Live Action TV

 * On Stargate SG-1 there is an Unas named Chaka. Or rather, that's what Daniel calls him, 'cause that's what he says most often. There's a language barrier, you see.
 * Anyang! In Arrested Development, Lucille Bluth adopts a Korean boy that doesn't speak English. He pretty much only says the word "Anyang," which means "hello" or "how do you do" in Korean, and the Bluths decide that it is actually his name. Whenever he's present and one of them mentions Anyang, he usually says his name back (because that is the polite response if they were speaking Korean).
 * And it turns out his real name is "Hel-loh."
 * Count Blah from Greg the Bunny has an extensive vocabulary, but he's named after his Verbal Tic of saying "Blah" at the end of sentences.
 * Which did not go well when in-universe Executive Meddling made him change his name to Count A'ight, which he couldn't pronounce.
 * Nuh-Uh from The Little Rascals.
 * Go Go Sentai Boukenger: "ZUBAAN!"
 * Chantho from the Doctor Who episode "Utopia" precedes everything she says with "chan" and follows it with "tho." Apparently, leaving them out is rude where she comes from.
 * Possibly Dorothy "Ace" Mc Shane, who tends to shout "Ace!" when she's enthusiastic about something.

Music

 * Noodle of Gorillaz learned to speak English later on, but at the time she was mailed to the other band members, the only word of it she knew was "Noodle". So they decided to call her that.

Theater

 * There was a kids' musical where the main character's only phrase was "No Fibbin'," so that's what the other characters called him. It was pretty odd.
 * Nicely-Nicely Johnson from Guys and Dolls, who always says "nicely, nicely, thank you" when someone asks how he's doing.

Video Games

 * Nina in Breath of Fire: Dragon Quarter is named after the only sound her damaged vocal cords are capable of producing.
 * Although Gau from Final Fantasy VI can say quite a few words, his favorite seems to be "gau", a Japanese onomatopoeia for roaring.

Web Comics

 * Klik from Goblins.

Web Original

 * Amy Blue in the Sailor Moon Abridged Remix episode.

Western Animation

 * In an episode of Phineas and Ferb, the characters call an alien Meap because that's the only word he says (so that's how he replies when they ask his name). He gets hold of a translator mustache at the end of the episode, though.
 * Boo in Monsters, Inc. is a slight variant. Her real name is Mary, but she's just a baby and doesn't know how to introduce herself. 'Boo' wasn't the first word she said to Sully, but she screams it later.
 * Another Pixar example would be Bubbles the yellow tang from Finding Nemo, who gets his name from the treasure chest-shaped aquarium decoration that periodically spouts bubbles.
 * Goo in Foster's Home for Imaginary Friends got her name because her parents let her choose her name when she was born and the only thing she could say was "goo goo gaa gaa."
 * Tweety Bird of Looney Tunes in spirit - he doesn't actually tweet much, but, well, he's a canary.
 * Poof from The Fairly OddParents
 * Susan Strong on Adventure Time. Her first came from her trying to say "sun", and her last name came from saying she was strong.
 * South Park: Timmy is a wheelchair-bound kid who can only say his own name, slurring it with an "ah" instead of "y" at the end. However he says it with such differing inflections, etc. that other people can always understand what he's saying. "Timmah! Timmah, Timmah, Timmah, Timmah. Timmah? Timmah!"
 * His parents Richard and Helen are also wheelchair-bound and can only say their own names.

Tabletop RPG

 * The wyrm-corrupted Black Spiral Dancers from Werewolf: The Apocalypse were given a new name upon completion of their first dance around the black spiral, after the first sound they made. Mostly these new names are incoherent noises of rage or distress, but one notably unfortunate individual was named Parrupt, as the first sound she made did not come from her mouth...
 * KILLFRENZY, the Chaos-possessed starship from, guess it, Warhammer 40,000.
 * A semi-related example; In Magic: The Gathering, it is an obscure fact about goblins that they are named after the noise their mother made when giving birth to them. Though there wouldn't be a whole lot of creativity going into their names anyway, considering that goblins are born in litters, (giving them their iconic numbers) and are none too bright to begin with (giving them there iconic tactics).
 * The famous Dungeons & Dragons story of Noh. A DM had a group of adventurers enter a room with a couple of treasures and a little girl. The girl wasn't a real person, but a magical construct who could only say two things "No" and "Please don't take these items". The players, unsure of what to do, tried to ellicit more responses from her, but failed. Finally the bard tried playing a beautiful song, and rolled so high on his skill check that the DM had a single tear roll down the girl's cheek. The players immediately decide she's too adorable to leave behind and adopt her, naming her "Noh". The DM eventually allowed her to be granted a soul and a personality (and the ability to truly speak), but the name stuck.

Real Life
"Soon, it wasn't uncommon for him to introduce himself at a party and be greeted with "Oh, you're Butterscotch Dinosaur Pussy!""
 * Ernesto "Che" Guevara, nicknamed after the Argentine slang interjection "che", which he used a lot.
 * A famous patient in the field of expressive aphasia known as Tan could only produce the sound "tan". Paul Broca's research on Tan's brain after he died revealed extensive damage caused by Syphilis in a particular area of his brain, an area which would later be known as Broca's area. It is one of the parts of the brain responsible for the formation of words and coherent speech.
 * In many languages, dogs and other animals do go around saying what they are called in that language, such as "gau" for "dog" and "maau" for "cat" in Cantonese.
 * You get a number of birds named after the sounds they produce, like the chickadee, the whippoorwill, the bobwhite and the cuckoo.
 * And that isn't only the case in English: German: Kuckuck, French: Coucou (pronounce "coocoo"), Chinese: Xique (approximately: shee-chue-eh, a magpie).
 * Don't forget the Japanese Cicada-TsukuTsuku Boshi.
 * Gecko lizards. Their name comes from the fact that their chirps sound like they're saying "gecko gecko" over and over again.
 * The Tokay Gecko in particular makes the distinct "gecko gecko" chirp as well as a chirp that sounds like "tokeh"... which is where it got its name.
 * The coquí, a family of small tree frogs native to Puerto Rico, named for its distictive call, "co-KEE."
 * The Quagga (an extinct relative of the zebra) was said to be named after its call (or the Khoikhoi word for zebra)
 * South Africa has plenty more where that came from: tok-tokies (beetles that make that 'tok-tok' sound by thumping the ground with their abdomens), the Hadeda (an ibis that makes that call - a lot), repeating words like "now-now" for emphasis in common speech... I could list forever.
 * The Aracuan (yes, they actually do exist), a South American bird named after its distinct call.
 * The Greeks thought that the languages of everyone beyond their borders sounded like "Bar bar bar bar bar"—hence, barbarians. (Barbaros if you're talking to an ancient Athenian.)
 * In Germany, many dogs are named Bello, which may be derived from "bellen" (to bark).
 * According to Cracked.com's 5 Ways Life With Tourette's Is Way Weirder Than You Expect, some people with Tourette's are "catchphrase generators". Some tics, such as "butterscotch dinosaur pussy", become this: