If you have a group of people banding together to fight evil, or to cause it, then it's good to have a good team name that people will remember. If you can't think of anything else, then why not name yourself after the number of members you have, plus a nice adjective that describes you? Maybe try to tie it together in a pun, some Added Alliterative Appeal or something.
In the end, what do you have? Why, The Notable Numeral, of course!
This naming convention is popular in Real Life to describe people who make the news as a group, usually as either the victims of a crime or as the people arrested for a crime (often in historic/sensational cases of people who are believed to be wrongly accused, whose case seems to represent a broader issue or who grab the public's attention in some other way), such as the Buffalo Six and the West Memphis Three. The Other Wiki calls these "Quantified groups of defendants." Describing a single such defendant, usually fictional, as the something-or-other One is a Stock Parody.
This can get awkward when you have a change in membership (unless the net change is zero). When changing the name would be very difficult, you'll just have to live with the name being an Artifact Name due to the One Extra Member (or one less member, as the case may be).
Beware, if excess alliteration disturbs you, then it might be best to look elsewhere.
See also The Adjectival Superhero, where the adjective describes a person or team instead of a number—teams where the number specifies how many elements a plural noun has (for example, The Three Musketeers) more properly go under that trope. Can cross with Superhero Sobriquets if it's a nickname and not the team's proper name.
Examples:
- Motu Patlu: The theme song refers to the eponymous duo as "Motu aur Patlu ki jodi" ("the awesome twosome, Motu and Patlu").
- Noonbory and the Super 7: The Super 7, though they're rarely called that In-Universe, instead opting to go by "The Super Sensors" or "The Super Borys".
- Simple Samosa: The main characters are collectively called the "Chatpata Four" ("chatpata" means "spicy" in Hindi) in one of Hotstar's official episode descriptions.
- Yamucha's-Kung Fu Academy: The squid gang is collectively referred to as the Mountain Thieves F4, with the "4" referring to how there are four of them.
- Bobobo-bo Bo-bobo: The Battleship Five Quartet. Parodied, along with everything else under the sun in that series, by virtue of having six members. This fact perplexes their leader so much he fires them all.
- Boys over Flowers: The F4 Boy Band.
- Food Wars!: The Tōtsuki Elite Ten Council.
- Great Teacher Onizuka: The Onibaku Duo.
- Kingdom: The Six Great Generals of Qin.
- Koi Koi 7: The titular team, though there are only six of them.
- One Piece:
- The Eleven Supernovas.
- The Four Emperors of the New World (Yonkou).
- Seven Warlords of the Sea (Shichibukai)
- Tantei Opera Milky Holmes: Genius 4.
- Yes! Pretty Cure 5
- Tentai Senshi Sunred: Kishou Sentai Weather Three.
- The Seven Deadly Sins (Dix): It applies because the painting depicts the seven sins as anthropomorphic personifications who satirize inter-war German society.
- Batman:
- The Dynamic Duo, comprised of Robin and Batman.
- The Terrible Trio.
- Combat Kelly and his Deadly Dozen
- Dynamo5
- Fantastic Four:
- The titular team, of course.
- The Frightful Four, a group of Fantastic Four villains.
- The Four, the Alternate Company Equivalent and Evil Counterpart Fantastic Four from Planetary.
- The Great Ten, a China-based team of DC super heroes.
- Inferior Five: The Inferior Five are a humorous DC Comics superteam consisting of the offspring of more popular, powerful supers.
- Legion of Super-Heroes: The Fatal Five.
- The Mighty Thor: The Warriors Three.
- New Gods: The Deep Six.
- Secret Six.
- Spider-Man: The Sinister Six
- Teen Titans: The Fearsome Five.
- The Amazing Three
- Knights of the Dinner Table: The "Untouchable Trio" (plus one).
- Mandrake the Magician The 8 Gang. It was a global criminal enterprise with many members but broken up into 8 sub-gangs that each got their own story arc as Mandrake defeated them one by one over a period of years.
- The Keys Stand Alone: The Awesome Foursome.
- Big Hero 6
- Kung Fu Panda: The Furious Five.
- Puella Magi Madoka Magica The Movie: Rebellion: The five main characters refer to themselves during their transformation song as the Holy Quintet.
- The Dirty Dozen
- The Hateful Eight
- Kill Bill: The Crazy 88. There aren't 88 of them. They just thought it sounded cool.
- The Magnificent Seven (1960)
- Ocean's Eleven: Ocean's Eleven, Twelve, Thirteen and Eight.
- Pulp Fiction: Fox Force Five, the main characters of an in-universe failed television pilot of the same name.
Mia: Fox as in we're a bunch of foxy chicks. Force as in we're a force to be reckoned with. Five as there's one, two, three, four, five of us.
- The Return Of The Secaucus 7 (1980, John Sayles)
- The Terrible Ten: A series of short films in the 1940s and 50's.
- Enid Blyton: Her child detective series The Famous Five and The Secret Seven.
By work:
- Ali Baba: The Forty Thieves.
- Bigtime: The Fearless Five.
- Brennus:
- The Dark Five.
- The Savage Six.
- The Rabid Eight.
- Clubland Heroes: The Splendid Six. It's mentioned in the backstory that they were the Good Fellows Four before recruiting two new members; at the end of the story, there's a summary of how the various members moved on from the team, during which it becomes the Splendix Five, then the Splendid Three, before the remaining members give up and officially disband.
- Dirty Pair
- Hercule Poirot: The Big Four.
- Jim Button the Wild 13: The eponymous band of pirates. They are actually never more than twelve, they just epically fail at math.
- Snow White: The Seven Dwarfs.
- The Three Musketeers
- Water Margin: The 108 Righteous Bandits—108 being a number of major mystical significance throughout many eastern religions.
- Whateley Universe:
- 'The Three Little Witches', which is also the title of a story.
- Cardinal Sin's 'Seven Deadly Sinners' from "Silver Ghost, Golden Angel Part 2".
- Worm: The Slaughterhouse Nine, a team of psychopaths who later get way more than Nine members.
- Akumaizer 3
- Battlestar Galactica (2003): The "Final Five" and "Significant Seven" Cylons.
- Being Human: For an example of the trope applied to victims of crime, the "Box Tunnel 20"
- Blake's 7
- Community: The Greendale Seven.
- Lost: The Oceanic Six.
- Saturday Night Live: The Ambiguously Gay Duo.
- Super Sentai:
- Dai Sentai Goggle Five
- Chikyuu Sentai Fiveman
- Rescue Sentai GoGoFive
- Uchuu Sentai Kyuranger: Kyu means 9, but the team ends up with 12 members by the end.
- "Dynamite Magazine": The Dynamite Duo.
- AKB48:
- The group was originally planned to have three teams, each made up of sixteen members.
- Kami 7 (Seven Goddesses).
- The Beatles: The Fab Four.
- The Dave Clark Five
- Grandmaster Flash and the Furious Five
- The Jackson 5: Or 5ive?
- Marginal #4
- The Monkees: The Pre-Fab Four.
- The Rutles: The other Pre-Fab Four.
- The tenka goken, Five Swords Under the Heaven, are five real-life historical Japanese treasure swords.
- The Bible: The twelve apostles.
- EarthBound (1994): The Runaway Five, a team which apparently actually contains six people.
- Ensemble Stars!: The Five Oddballs, which later became the Three Oddballs when two of their number temporarily went into hiding.
- Deus Ex: Majestic 12.
- The Elder Scrolls: The Nine Divines of Tamriel, nine (originally eight, later joined by a Deity of Human Origin) divine beings who sacrificed portions of themselves to create the mortal world. Phrases like "By the Nine" are used like "Oh my god".
- Final Fantasy XIV: The Ehcatl Nine, so named because it sounded better than "Ehcatl Twenty-Or-So".
- Hitman (2016): The Sarajevo Six, formerly a squad of mercenaries who fought in The Yugoslav Wars, presently a bunch of fugitive war criminals.
- Killer7
- Kingdom Hearts: Organization XIII.
- Mission Impossible (1990): The Sinister Seven. Although it's never said who they really are.
- Paper Mario 64: The Fearsome 5.
- Sly Cooper and the Thievius Raccoonus: The Fiendish Five.
- Twisted Wonderland: The Great Seven are a group of seven notable Disney Villains, who are revered in-universe historical figures.
- The Wonderful 101: The team in the game is actually called the "Wonderful 100" (with 100 pronounced as "one-double-oh"). The trailer states that the extra 1 represented the player, but at the end of the game the team gains a new member and officially becomes the "Wonderful 101".
- TV Tropes: Tropes that follow this naming convention include My Hero, Zero, The Chosen One, Those Two Guys, Freudian Trio, Power Trio, and Terrible Trio.
- Avatar: The Last Airbender: "The Fearsome Foursome!".
- Bionic Six
- Darkwing Duck: The Fearsome Five.
- My Little Pony: Friendship Is Magic: The Mane Six.
- The Super 6
- Teen Titans (2003): The H.I.V.E. Five, the animated version of the Fearsome Five.
- The Tick: The Civic-Minded Five.
- Wacky Races: The Gruesome Twosome.
- Winx Club: In a sense, the Trix, as they are a Terrible Trio of witches and Trix alludes to both the number three (the tri- prefix) and the -trix feminine Latin suffix (of praecantrix).
- The Original Six (NHL hockey teams).
- The NCAA basketball conference The Atlantic 10, also currently with 14 members and 2 "affiliates" (schools that only compete in the conference in 1 or 2 sports).
- College basketball's Final Four.
- The Big 12, currently with 10 members and 11 "affiliates" (schools that only compete in the conference in 1 or 2 sports).
- The Pac 12, currently with 12 members and 4 "affiliates" (schools that only compete in the conference in 1 or 2 sports). (As noted above, membership changes can make this trope very awkward.)
- The Big Ten, currently with 14 members and 2 "affiliates" (schools that only compete in the conference in 1 or 2 sports).
- The NCAA March Madness college basketball brackets: Sweet Sixteen, Elite Eight, and Final Four.
- In sports, Michigan basketball's Fab Five.
- The Famous Five. Who were a bunch of Canadian feminist icons; sadly, they aren't that famous.
- DV8: In-universe, they're called the Deviants, which is much more appropriate since it's rare for all 8 members to be active at once. "DV8" was probably just easier to trademark when it came time for them to get their own comic.