A classification is made that doesn't make any sense at all. The categories overlap, are on different levels of abstraction, or something along those lines.
Note that for a classification to be this trope, the division must be nonsense in itself. A valid division presented in a humorous way is something else, for example Gratuitous Latin.
Likewise, a classification with heavy Unfortunate Implications of Fantastic Racism or similar (such as All Gays Are Pedophiles or Aliens Are Bastards) is another kind of nonsense - not this trope. Same goes for sets of food groups that are merely unhealthy or alien. While a nonsense classification of food groups is likely to also be unhealthy or alien, the thing that makes it this trope is that the categories overlap, mix levels, or similar.
- In Elf, Buddy says that elf food tries to include "all the food groups": candy, candy canes, candy corn, and syrup.
- Jorge Luis Borges' fake Chinese encyclopedia Celestial Emporium of Benevolent Knowledge, with its classification of animals: (a) those that belong to the emperor; (b) embalmed ones; (c) those that are trained; (d) suckling pigs; (e) mermaids; (f) fabulous ones; (g) stray dogs; (h) those that are included in this classification; (i) those that tremble as if they were mad; (j) innumerable ones; (k) those drawn with a very fine camel's-hair brush; (l) etcetera; (m) those that have just broken the flower vase; (n) those that at a distance resemble flies.
- The Discworld food groups: sugar, starch, grease, and burnt crunchy bits. It says something about the strangeness of the Discworld that on that world, all four of these things can be dug out of the ground.
- Ponder Stibbons' attempts at cladistics (really closer to phenetics) lead to conclusions such as "the banana is actually a fish", because there are fish which are yellow and travel in "bunches".
- Types of rock the Dwarfs have a name for (overlapping with Translation: "Yes" because these are a single word in Dwarvish) include "rock which just hit me on the head" and "rock which looked really interesting and which I swear I left here yesterday."
- The Areas of My Expertise plays this card a few times. For example the column on "food, drink, and cheese", where there are "only so many kinds of foods to write about", namely "abs, polar bear steaks, chili, chili, and polar bear steaks."
- The Doctor Who episode Closing Time features a baby named Alfie (aka Stormageddon, Dark Lord of All) who classifies all humans into four categories. "Mum", "Not Mum" (his father Craig), "Also Not Mum" (the Doctor) and "Peasants". By the end of the episode, he and Craig have grown close enough to allow for a "Dad" classification. His first word is also "Doctor", indicating he may have eliminated the "Also Not Mum" category as well.
- Mutant UA: Pyrisamfundet doesn't like to have a forbidden zone in the middle of their nation. They feel it's embarrassing. So they decided that it isn't a real forbidden zone. Sure, it's an ash-desert full of monsters and mysterious phenomena - but hey, this area is geographically shaped like a square. Real forbidden zones are round!
- That's the in-universe reason. The reason beyond the fourth wall is that the authors wanted to make another forbidden zone, but they had already released an official map where all the zones were listed. retconning the map into being unreliable for political reasons solved that problem quite elegantly.
- Plants vs. Zombies has an "suburban almanac" that describe all the different plants and zombies in the game. This encyclopedia, not taking itself very seriously, keep mixing up the concept of "individual" with the concept of "species". We also have the zomboni who is not a zombie but an alien who likes to hang out with zombies and the zombie yeti, who we don't know anything about... except for his name, birth date, social security number, educational history, past work experience and sandwich preference (roast beef and Swiss).
- Being an expy of the above, Mini Robot Wars has the "Robopedia" that describes all the different Minirobots (good guys) and Machines (bad guys) in the game. Unlike the suburban almanac, there isn't too much mix-up of the concept of "individual" with the concept of "species", as every single one of them are technically mechanical and very few of the entries show backstories. Some of the Minirobot entries give info on what they do, what they're like, reasons for fighting, and so on. For the Machines, in addition to showing their primary duties, their entries also give some of their extra duties (Jetpackers also write messages in the sky, Cyclers also deliver pizza, Knights' favorite game is chess, etc.) or fun quotes ("Where's the clock?!" for the Time Bomb).
- Final Fantasy XIV divides all creatures into several "something-kin" categories. Much like early Real Life taxonomy, these mostly make sense, provided you don't look too hard at the edge cases — perhaps most notably, due to Fantastic Racism, the various beast tribes are not classified as "spoken", despite obviously meeting the qualification of "sapient humanoid". And then there's the one hapless scientist who campaigned to get ducks classified as "spoken", despite the fact that they are clearly "cloudkin" (i.e. birds), on the grounds that their quacks were supposedly "a highly developed language beyond the comprehension of mankind".
- Zinnia Jones attributes this trope to Rick Santorum in "A napkin is not an argument: Deconstructing Santorum."
- The Simpsons
- Dr. Nick's recommendation, when Homer wants to gain weight: "You'll want to focus on the neglected food groups such as the whipped group, the congealed group and the chocotastic!" See page illustration above.
- An early commercial featuring Bart Simpson has him explaining the basic four food groups: sandwich group, cow group, jungle group, and Butterfinger group.
- Reverend Lovejoy at one point summarizes the major world religions as "Christian, Jew, and (looking at Apu) miscellaneous."
- Garfield and Friends: According to Garfield, the four basic food groups are: pasta; cheeseburger with fries; chocolate cake; and more pasta.
- Played for Drama in Star vs. the Forces of Evil: One of Star's complaints about Mewni's treatment of monsters is that there's no consistency as to which (sapient) species are counted as "monsters". It includes a wide variety of disparate groups (from frogmen to Lizard Folk), but excludes many likewise inhuman races that Mewni consider allies and equals (like the pony heads, the sapient pigeons, and even demons). The actual definitions are technically decided by the Royal Monster Expert, but she's a doddering Know-Nothing Know-It-All. It's all but stated that "monsters" is just a grouping made up to disparage all the peoples the Mewmans could conquer and oppress, leaving out the ones they had to respect as allies.
- The oldest Polish encyclopedia, most famous for its definition of a horse: "Everyone can see what a horse is like" also contained this sentence "Goat: A goat is an animal of the stinky type."
- Conrad Gesner's classification of minerals. Includes "Those whose forms are based upon, have some relation to, or suggest the geometrical conception of points, lines or angles", "Those which bear a resemblance to certain artificial things" and "Stones which derive their names from birds".
- If we include ministerial divisions,note the Secretary of State for the Southern Department from pre-1782 Britain definitely counts (as would the more junior Northern Department). As The Other Wiki says: "The Secretary of State for the Southern Department, the more senior, was responsible for Southern England, Wales, Ireland, the American colonies (until 1768 when the charge was given to the Secretary of State for the Colonies), and relations with the Roman Catholic and Muslim states of Europe. The more junior Secretary of State for the Northern Department was responsible for Northern England, Scotland, and relations with the Protestant states of Northern Europe."
- Prior to the creation of the U.S. Department of Homeland Security, the U.S. Treasury Department held authority over some seemingly random national security obligations, including command of the Secret Service. This is because the Secret Service was originally created to combat counterfeit currency after the Civil War (a responsibility they still hold to this day) and gradually gained more responsibilities. Before they were created, the FBI and IRS's duties belonged to the Secret Service.