One of the very few negative things about cats is that, barring hairless cats, they cough up hairballs. This is because they lick themselves clean and end up swallowing a lot of fur, thereby needing to hack it up. It is particularly common for long-haired cats as they logically swallow more fur.
However, writers sometimes see one good thing about cats coughing up hairballs: it's an opportunity to make some gross-out jokes. This might be popular because cats are generally quite elegant and composed, so it could be used as a quick way to temporarily bring down the dignity of a cat for comedic effect. There's also the fact that, unlike when a human vomits, coughing up hairballs is actually normal for cats, so they can have the moment of gross-out humor without making anything too bad happen to the cat.
Sometimes, if people don't like cats, are a snob/Neat Freak, are an incompetent cat minder, or are dealing with a mean cat, the hairballs might be one thing they complain about. They might also show an anthropomorphic cat coughing up a hairball to remind the audience that they are still a cat. If they want to go into really gross territory, they might have people find things in the cat's hairball.
- In Cats Are Weird, one strip has Misty the cat cough up a hairball on the ground, much to the disgust of her owners.
- In Shrek 2, Puss in Boots tries to assassinate Shrek, but then pauses to cough up a hairball, which grosses even Shrek out.
- In Puss in Boots, Humpty Dumpty declares that "Humpty and Puss" completed their mission. Kitty is offended that he excluded her and goes to bed early, saying that she has a hairball as an excuse.
- Parodied in The Stinger for Captain Marvel (2019). Goose, a catlike alien, coughs up the Tesseract she swallowed earlier.
- In The Cat in the Hat, the title character coughs up a hairball into his hands, then throws it onto a statue, grossing Conrad and Sally out.
- In The Smurfs, Azrael coughs up some of Smurfette's hair he swallowed during a fight with her, which leads to Gargamel using it to make Smurf Essence.
- In Charlie and the Chocolate Factory, one of the gross things mentioned in the song about Veruca Salt is "a thing the cat left on the stair".
- In one of the Skippyjon Jones books, Skippyjon is asked to solve a riddle but he can't think of an answer and coughs up a hairball instead. The dogs think he has a virus and make up a limerick about it.
- In the Warrior Cats book "Into the Wild", Sandpaw is being rude, so Lionheart says, "She must have a hairball somewhere".
- In Star Trek: The Next Generation, Geordi, who is inexperienced with cats, tries to look after Data's cat Spot, but then gets angry at Spot because the cat broke Geordi's lamp and then coughed up a hairball under his bed.
- In Socks in Space, an online game based off Martha Speaks, some aliens that look exactly like cats throw weaponized hairballs.
- The Elder Scrolls Online has skill lines where various NPCs send you crafting materials attached to humorous letters. One such letter asks, "Do you know anything of Khajiit etiquette? What is the proper way to respond when your host coughs up a hairball at dinner?"
- Crappy Pictures: In one post talking about the annoying parts of having pets and children at the same time it's mentioned that sometimes, her toddler son is curious about their cats' hairballs.
- In the Arthur episode "Pets and Pests", Nemo is hired to kill a mouse that's loose in the Reads' house. Pal is not impressed with Nemo staying over, especially when Nemo says, "I cough up fur balls at night."
- The opening to CatDog features a portion of Cat licking his fur. However, rather than him coughing up the hairballs, the hairballs come out of Dog.
- In The Loud House episode "Along Came a Sister", Lincoln is looking after his teacher's pet tarantula Frank. The kids see a hairball that their cat Cliff coughed up and mistake it for Frank's corpse, only realizing Frank is alive when Cliff coughs up another hairball that looks just like it.
- Martha Speaks: In "Martha Takes the Cake", the kids have a phony trial to determine if it was Martha the dog or Nelson the cat who ate a bite of Alice's birthday cake along with a candle. It's revealed to be Nelson, via a candle being in his hairball.
- In the first episode of The Oblongs, as befits the show's style, Lucky the cat literally coughs up a lung, which is at first mistaken for a hairball.
- Being the original Grossout Show (and because one protagonist is a cat), The Ren & Stimpy Show has a lot of hairball jokes.
- In the pilot episode "Big House Blues", Stimpy coughs up hairballs all over Ren. He's at first angry, until a little girl comes to adopt him because the hairballs make him look like a poodle.
- "The Cat Who Cried Rat" has Stimpy cough up what at first looks like a hairball, but turns out to be Ren, who was in Stimpy's mouth after passing himself off as a mouse.
- "The Cat That Laid The Golden Hairball" revolves around hairballs somehow becoming more valuable than gold. Ren sets up a production line for Stimpy to cough up hairballs continuously. Eventually, poor Stimpy is left not only hairless, but also unable to cough up any more hairballs from being overworked.
- There is a song called "Cat Hairballs". It has a premise fairly similar to The Cat That Laid The Golden Hairball, with Ren setting up a conveyor belt for Stimpy to "Hwarf" up hairballs onto while the former stamps them with approval. Though in this case they also sing about what they'll make out of the hairballs, like high heel shoes, a hat and matching underwear. Much like the episode that inspired it, by the halfway point Stimpy is starting to run out, licking at spots that have been farmed dry and gasping for breath. At the end, an overworked and completely licked clean Stimpy tries to hwarf one last time and passes out on the conveyor belt. Ren then says "That's disgusting" and stamps Stimpy's butt with a painful hluarf sound, indenting it with a Butt Brand, which the video iris out on.
- In the Rugrats episode "Babysitting Fluffy", Chuckie and his father are babysitting Angelica's cat Fluffy, who coughs up a hairball on Chuckie's shirt. Phil, who previously thought he didn't like cats, says, "I guess I do like cats!".
- The Simpsons had Snowball II (named after the first one they had, who was already white), a black cat who became part of the family for a long time, and also known for throwing hairballs up as seen in most of her artworks. This is even lampshaded in the Trading Card Game by Skybox where a mini-collection of scratch-and-smell cards have one about how it smells a Snowball's hairball.