Perplexing Plurals

"Yes, Shaniqua. She was a dominatrix. Because, you know, wrestling needs dominatrixs."
"Dominatrixes?"
"Dominatrixi?"
"Whatever."

— RD Reynolds, WrestleCrap^note It's "dominatrices", if you're wondering.

Part of what you know when you know a language is how to make your words fit into a grammatical system. This can be fairly simple, as in English (the odd -s here, the odd -ed there) or fairly complex, as in the Russian case system. One thing all systems have in common though, is that they work all the time. For every singular, there is a plural.(Though there are cases where there is neither.) It might be regular (trope, tropes) or irregular (goose, geese), but you know it's there and you know what it is.

...until you find yourself needing to talk about octopuses...octopus...octopi- no, that's Latin...octopodes? Ugh, now this is going to bother you all day.^note The fact that all three plurals given in this example are considered correct doesn't help.

Sometimes you go for a plural and...there isn't one. Maybe it's an unfamiliar word, maybe you've heard different options and don't know what to pick, maybe language is just screwing with you. Whatever the reason, it feels so overwhelmingly wrong that you have to stop and talk about it. Almost always derails the conversation at hand, and may be the equivalent of a Logic Bomb to a Grammar Nazi.

Truth in Television. English has borrowed rather large number of plural forms from other languages, most notably Latin (alumnus/alumni, formula/formulae), Greek (phenomenon/phenomena, stigma/stigmata), French (tableau/tableaux), while also retaining plural forms from archaic English (goose/geese, ox/oxen, cow/kine ^note known to trivia nerds as the only word where the plural and singular forms share no common letter). Related to the phenomenon of "paradigmatic gapping" in Real Life, where a grammatical form that logically should exist just...doesn't.^{case in point...}The proverbial example in English is the verb "can", which can be used in the present or the past, but not in any other tenses. You just can't say "I will can do X", you need to use something like "will be able to" instead.

Note: This is crucially not a trope used by Funny Foreigners. It is confusion about a speaker's own language (and the need to stop and work it out) and usually not caused by ignorance or Book Dumb (although expect a character beset by Sesquipedalian Loquaciousness to be immune). See Pluralses.

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Examples:

Comedy

• Brian Regan has a routine built around this trope. It starts with "boxen" (like oxen) of donuts and just snowballs from there.
• Richard Lederer's "Foxen in the Henhice" is based around the same concept.

Comic Strips

• Once in The Far Side, an octopus addresses a lecture hall full of his fellows — and even he can't figure out what the plural is.
  "Fellow octopi, or octopuses...octopi?... Dang, it's hard to start a speech with this crowd."

Fan Works

• In Cartographer's Craft, a Harry Potter fanfic by copperbadge, Hermione insists on using "Horcruces" as the plural of "Horcrux" instead of "Horcruxes", to everyone else's chagrin.
• A minor Running Gag in It's A Dangerous Business, Going Out Your Door involves Rarity automatically correcting Rainbow Dash whenever the latter says "pegasuses" instead of "pegasi". Applejack eventually gets sick of the argument and tells Rainbow Dash to use "pegasi" and Rarity to stop being so uptight about it.

Films — Live-Action

• Mystery Men: Captain Amazing comments to Casanova Frankenstein that they have always been each other's greatest "nemisises..nemisi..." (It's "nemeses," as Casanova points out.)
• The Witches (2020) has this exchange after the three mice escape the Grand High Witch:
  Bruno: Why are we mouses?!
  The Boy and Daisy: Mice.
  Bruno: Whatever!
• In The Muppet Christmas Carol, the muppet mice try both "mouses" and "meeces"!

Jokes

• Some Russian jokes deal with the unpredictable nature of Russian plural nouns. An example from Wikipedia:
  The genitive plural of a noun (used with a numeral to indicate five or more of something, as opposed to the dual, used for two, three, or four, see Russian nouns) is a rather unpredictable form of the Russian noun, and there are a handful of words which even native speakers have trouble producing this form of (either due to rarity or an actual lexical gap). A common example of this is kocherga (fireplace poker). The joke is set in a Soviet factory. Five pokers are to be requisitioned. The correct forms are acquired, but as they are being filled out, a debate arises: what is the genitive plural of kocherga? Is it Kocherg? Kocherieg? Kochergov?... One thing is clear: a form with the wrong genitive plural of kocherga will bring disaster from the typically-pedantic bureaucrats. Finally, an old janitor overhears the commotion, and tells them to send in two separate requisitions: one for two kochergi and another for three kochergi. In some versions, they send in a request for 4 kochergi and one extra to find out the correct word, only to receive back "here are your 4 kochergi and one extra."
• There's an old Italian joke where a man doesn't know if the plural for "Belga" (a person from Belgium) is "Belghi" or "Belgi". He eventually resorts to write down "Un Belga. Anzi due!" ("One Belgian. I mean, two!") (According to Google translate, "Belgi" would be correct if they were all men, while it would be "Belghe" if they were all women. There doesn't appear to be a gender-neutral form.)
• There's a joke about someone shipping a pair of mongooses to a zoo and being unsure of what the plural of "mongoose" is. They start out writing a note referring them to "mongooses", then try "mongeese", and eventually resort to writing "Enclosed is the mongoose you ordered. Also enclosed is the other mongoose you ordered".

Literature

• In Good Omens, Shadwell's instructions to Newt are to search for:
  1. Witches.
  2. Unexplainable Phenomenons. Phenomenatrices. Phenomenice. Things, ye ken well what I mean. ^note He means "phenomena", of course.
• Since the climax of The Pyrates occurs at the aptly-named Octopus Rock, the inevitable confusion ensues. Antihero Colonel Blood uses the incorrect Latinate plural "octopi", and smarmy hero Captain Avery offers him the correct (though antiquated) Greek "octopods" or "octopodes". Largely out of contrariness, Blood elects to go with "octopussies".
• The Dresden Files:
  • In book six, Harry Dresden figures out some of the players in the mystery, and comments that "we were dealing with a succubus. Or more than one, which for grammatical reasons I hoped was not the case." (It's Succubi, by the way.)
  • In another book, Harry is at a charity art auction when he runs into Gentleman Johnny Marcone. Trying to distract Marcone, Harry mentions that he's there because he collects velvet Elvises, or as he prefers to call them, velvet Elvii, since the proper pluralization tends to lead to his Gollum impersonation.
• Discworld:
  • In the Post Office Diary, a public statement by the Post Office apologising for the fact some mail has been defecated upon by mongooses (which were deliberately placed in the post boxes to kill the snakes, which were deliberately placed there to eat the toads...) is followed by one saying that they've been following the mongooses/mongeese debate in the Ankh-Morpork Times with interest, but don't feel it's really the point.
  • When Lord Rust is looking at the map of Klatch in The War Room in Jingo:
    There were the little square boxes for the towns and cities, and cut–out palm trees to indicate the known oasisies. And, although he was uneasy about the word 'oasisies', Lord Rust looked at it and saw that it was good.

Live-Action TV

• The Brady Bunch: The B Plot of the episode "The Personality Kid" concerns Bobby & Cindy going ape-shit over safety. The following concerns some electrical outlets in the kitchen, which have so many extensions & multi-prongs plugged in that one is referred to as an "octopus".
  [Bobby hands Carol a new plug]
  Carol: Now I hope these are the right plugs.
  Bobby: Just the kind the teacher said to get instead of that old octopus.
  Alice: Do you know that all last night I dreamed about octopuses?...Octopussys?...Octopi?
• In Buffy the Vampire Slayer:
  • Riley comments that, after falling in with the main characters, he suddenly finds himself needing to know the plural of "apocalypse". (It's "apocalypses", by the way).
  • In the 6th-season's "Gone", Warren declares to Buffy that "We are your arch-nemesises...ses." When they fail to open their escape door, Buffy mockingly says to Willow: "I give you my arch-nemesis...ses...ses." It became a Brick Joke when a vampire the next season said it was "nemeses," which Buffy duly noted.
  • In the seventh season, Willow tries to assemble the ingredients for a spell:
    Willow: OK, I got my tumbleweed, my eggs, got my chrysalises...chrysali...? My butterfly transformer pods.
• The girls of iCarly spend a fairly large amount of "iGo to Japan" arguing of the current plural of the word "possum". The episode suggests "single possum, multiple possi". The correct plural is indeed possums
• There is a variant of this in Arrested Development. GOB has just chipped a tooth, causing him to whistle his S's, and is dense enough that he think he can avoid using an "S" by switching to a different plural noun.
  GOB: I have a few terms (whistle)... I mean conditions (whistle)... I have one term and one condition.
• In the Honey, I Shrunk the Kids episode "From Honey, with Love", the family briefly gets into an argument over the correct plural of "moose". Nick produces the correct answer: "The plural of 'moose' is 'moose'. Like 'sheep', or 'deer'."
• The Big Bang Theory: Raj tells Leonard and Howard that he hopes they fall down and break their 'coccyxes'. Sheldon corrects him that the plural of 'coccyx' is 'coccyges'.
• House of Anubis: When Patricia offers to "share" Eddie with Mara and have him be a shared nemesis, she trips up in trying to figure out what the plural of nemesis would actually be. She ends up just going with "arch enemies".
• In the Surgical Spirit episode "The Locum", one character claims that the plural of locum is "loca". Shelia counters this with "museums", "chrysanthemums" and "dum-dums".
• Castle: In one episode, the team is interviewing a mother-daughter witness pair whose last name is Casillas. Castle, being interested in language, points out that it's a hard name to possessive-pluralize, as it would be "Casillases's." This leaves Ryan confused how to just pluralize it, causing him to stick on too many "esses."
• Gilmore Girls: At one point, Rory and Lorelai debate the proper way to pluralize "cul-de-sac." Rory (correctly) argues that it's "culs-de-sac," while Lorelai prefers "cul-de-sacs."
  Lorelai: "That doesn't sound like English."
  Rory: "That's because it's French."

Music

• Used in the novelty song "I Want a Hippopotamus for Christmas."
  I want a hippopotamus for Christmas
  Only a hippopotamus will do
  No crocodiles or rhinoceroseses
  I only like hippopotamuseses
  And hippopotamuses like me too!
• The Allan Sherman song "One Hippopotami" (a parody of "What Kind Of Fool Am I?") is half this trope and half "pair" puns.
  One hippopotami cannot get on a bus
  Because one hippopotami is two hippopotamus
  And if you have two goose, that makes one geese
  A pair of mouse is mice, a pair of moose is meese
• "The Hippopotamus" by Flanders and Swann not only pluralises it as "hippopotami" and "hippopotarmy", but also claims the female of the species is a hippopotama.

Podcasts

• An odd inversion occurs in Jemjammer where Cacophony briefly uses "octopi" to refer to a singular sewer octopus.

Puppet Shows

• The Dark Crystal
  • Though no one in-universe is unaware of this, the word "Skeksis" is both singular and plural; the singular is pronounced "skek-siss" and the plural "skek-sees".
  • While the original film uses the plural "Gelflings", the prequel series The Dark Crystal: Age of Resistance, in just one of several linguistic retcons to enhance the world's whimsy, uses "Gelfling" as both singular and plural.

Radio

• Our Miss Brooks: How do you reference two men with the same surname? In "Mr. Boynton's Parents", nervousness sees Miss Brooks momentarily confused as to the correct manner in referencing Mr. Boynton and his father:
  Miss Brooks: Where's Mr. Boynton? Or should I say where are Mr. Boyntons . . . or Misters Boynton . . . where's everybody?
• The Ricky Gervais Show: Ricky once relayed a story where he asked Karl what the plural of "mongoose" was, saying that most people would say it's "mongeese" when it's actually "mongooses". Karl's answer? "Mongs".
• In one episode of More of Less, the BBC Radio 4 show about numbers, presenter Tim Harford bemoaned that his other employer, the Financial Times, was bowing to popular usage and treating "data" as singular, rather than the plural of "datum". Amongst the replies he got from listeners disagreeing with his position was one saying that everyone who didn't like it could stick their pedantry up their ba.

Tabletop Games

• Dungeons & Dragons:
  • Apparently the plural form of "slaad" is not "slaads" but rather "slaadi".
• Warhammer 40,000:
  • The Tyranids have the Carnifex. Good luck getting the fans to agree on a plural.
  • The plural of "codex" (the name for a faction army book) is another one. Although "codexes" is used officially, many prefer the correct Latin form "codices" (and, likewise, will use "carnifices" to pluralise carnifex, also correct Latin). Given that many things in 40k get pseudo-Latin names that don't abide by traditional Latin grammatical rules, this might actually be less appropriate.
• In Magic: The Gathering, a powerful mana-generating card is the Mox (Mox Ruby, Mox Sapphire, and so forth). Traditionally, the plural is "Moxen".

Video Games

• At one point in Assassin's Creed II, Desmond loses his focus when wondering what the plural for "animus", the machines that allow him to experiece his ancestors' lives, is.
• In Chrom and Sumia's A Support in Fire Emblem: Awakening, Chrom isn't sure if the plural for "pegasus" is "pegasuses" or "pegasi". He then settles on the latter in their S Support.
• Nobody in the Freespace fandom is sure what the plural of "Sathanas" is supposed to be (given that it's an alternate name for Satan, it probably doesn't have one). Expect to see "Sathanai", "Sathanes", or "Sathanaseses" depending on the fan in question. The game itself avoids the issue by always referring to that ship class as "Sathanas juggernaut(s)".
• Kingdom of Loathing tends to have a lot of fun with plurals, with "box" becoming "boxen", "kiwi" becoming "kiwus", "fruit basket" becoming "fruits basket", and "liar's pants" becoming "liar's pantses, precious". Items which you can only legitimately have one of tend to have plurals calling No Fair Cheating; for example, the plural of "Staff of Ed" is "Staves of Ed, you dirty exploiter you".
• Pokémon averts this by making the plural names of all Pokémon species, as well as "Pokémon" itself^note despite being an abbreviation of "Pocket Monsters", unchanged from the singular versions. Not that this stops some people from referring to "Pokémons" or "Pokeymans".
• While never mentioned in-universe, there are occasional Edit Wars on the Resident Evil wiki about the plural of "Cerberus". Since "Cerberus" is the Latin form of the Greek "Kerberos", the Latin plural "Cerberi" is probably correct. Since the word is being used as an English word here, some people (and dictionary.com) might say "Cerberuses" is also acceptable. ^note Apparently, the plural of the Greek "Kerberos" is "Kerberoi".

Webcomics

• Dumbing of Age: Joyce mocks her own judgmental tendencies by jokingly asserting that the plural of "hanky-panky" is "hankies-panky".
• In the Alt Text for the xkcd strip "Mimic Octopus Randall says that he's resisting "octopi" because there's a scene in Lost Boys by Orson Scott Card that hinges on it being incorrect.

Web Original

• SCP Foundation states right that the beginning of the Nexus Hub that the correct plural is "Nexuses." The reasoning for this is fully explained in the page discussion.

Western Animation

• In one episode of Kim Possible Drakken buys a Weather-Control Machine drains a lake for water, and he comments on the machine not filtering out all the "fishes". This launches an argument between him and Shego about what the plural of fish is. Shego tells him that both fishes and fish are correct plurals for the word.
• In the Phineas and Ferb episode "Greece Lightning", the narrator of an educational filmstrip is unsure how to refer to platypi. Platypuses. Platypeople? Early on the episode, Major Monogram is just as confused and expresses it the same way the narrator does.
  • Discussed in the episode "Primal Perry", when Dr. Doofenshmirtz and his hired muscle Liam O'Kraken get sidetracked over whether the correct plural is "platypuses" or "platypi". Liam explains the former, despite sounding wrong, is the more correct term, but the latter is still acceptable.
• In Teen Titans, Control Freak gets stuck on the plural for "nemesis" in one episode.
• In The Simpsons, Principal Skinner at one point refers to "hypothetical dogs and poni".
• My Little Pony: Friendship Is Magic took a while to commit to a standard plural form of "pegasus", initially copping out and using "pegasus ponies" before settling on "pegasi". In "Hearth's Warming Eve", Chancellor Puddinghead, as played by Pinkie Pie in the Hearth's Warming Eve pageant, gets confused and calls them "pegasus-es-es."
• An episode of Hercules involving the crew of the Argo had an argument over the plural of cyclops, with most of the suggestions being similar to plurals of "octopus". Ironically, the one a person stated most authoritative ("cyclopi") is the only one that wasn't right.
• The Sultan's advisors in Hugo the Hippo can't agree on the plural of "hippopotamus", suggesting "hippopotamuses", "hippopotami", and even "hippopotamus", before the Sultan cuts the Gordian knot and calls them "hippos".
• Mr. Jinks hates meeces to pieces!
• Miraculous Ladybug: It hasn't come up in the show yet, but the fandom cannot for the life of them agree on the proper plural of "Miraculous".
• In the Ultimate Spider-Man episode "Strange Little Halloween", Spidey gets hung up on the plural of "nemesis", suggesting "nemesises" and "nemesi". Ant-Man tells him it's "nemeses", and he says that doesn't sound right.

Real Life

• Hacker jargon plays with this a lot; one of the more prominent examples is the old Digital VAX minicomputer. Although not completely universal, the plural VAXen is common. Other plurals common in the computing world are Unices, the plural of Unix, and boxen, the plural of box. Both are tongue-in-cheek, of course.
• Weetabix. Is the plural Weetabix or Weetabices?
• Once upon a time, in the days of USENET, there was a discussion on sci.lang about the proper plural of Elvis, a useful discussion, since impersonating Elvis is an industry. The majority would have the plural go like pelvis, that is Elves. A respectable minority found a Greek declension class for the purpose and opined that Elvis in the plural should be Elvides. Neither side admitted the plural Elvises, nor for the matter Elvii.
• The plural form of dwarf has been subject to some debate. Until the early to mid-twentieth century, dwarfs was more commonly used in most contexts. Then J. R. R. Tolkien set a precedent within the fantasy genre by referring to his dwarf characters as dwarves. Since then, dwarves has become the standard plural for the fantasy creatures that we all know and love (Disney, Discworld, and Warhammer being notable exceptions). On the other hand, dwarfs is still used within scientific contexts in Real Life. For example, dwarf stars and small organisms are referred to as dwarfs — although when talking about humans with dwarfism, little people is considered more polite nowadays.
• Utterly and completely defied in Finnish, where the standard Finnish grammar is consistently enforced even among loanwords. This is even considered to apply to trademarked names, thus even if a made-up word isn't supposed to have a plural form it does have one even in official Finnish translations (e.g. "jedit", "sithit"^note  Also, certain nouns that are capitalised in English are not in Finnish, such as nationalities ('norjalainen') or members of religious groups ('ortodoksi'). Both the Jedi and the Sith are considered to belong to the latter category. or "Pikachut").
• Officially, there are no such things as Legos. LEGO is an uncountable noun, as in "some Lego", and the countable items are "pieces of Lego" or "Lego bricks". To someone used to this, "five Legos" sounds like referring to kernels of sweetcorn as "five sweetcorns".
• Another puzzling aspect of the Puzzling Platypus — like the octopus example above, is it "platypuses", "platypi", or "platypodes"?
• David Langford has had two recorded issues with the question of "more than one Deus ex Machina". The first time he started with "about three deus ex machinas", altered this to deuses ex machina and then dei ex machina, before his wife, who's a linguist, told him it was di ex machina. And then the editor decided it was deus ex machinae. The second time was an argument with Peter Nicholls while compiling the SF Encyclopedia over dei ex machina or di ex machina, which led to a Running Gag at Mexicon 5, as their Nicholls-inspired mascot was credited with all kinds of incorrect plurii.

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Incidentally: Dominatrices, from the Latin, and octopodes, from the Greek. But since by now they're both old and familiar enough to be considered English words, there's also nothing wrong with dominatrixes or octopus(s)es.

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