A Comedy trope. A character, nervous at the sight of something, will begin to bite their nails really fast in order to try to calm themselves. In Western Animation, this will more often than not result in a flurry of nail clippings due to the sheer rapidness of the nail-biting, often with a typewriter sound effect. This trope is often used by a Cowardly Lion, Lovable Coward, or a Nervous Wreck.
- In Hercules, Pegasus actually does this with his front hooves, during the "One Last Hope" number when Hercules goes through the dangerous obstacle course that Phil set up as part of his training to save a damsel in distress.
- The Terminator. Sarah Connor is chewing her nails while watching a police video of Kyle Reese's interrogation.
- In Ice Age 3: Dawn of the Dinosaurs, one of the possum twins bites off his own nails, then his brother offers him one of his hands so he can continue biting.
- Doubt Academy: When Momoko Kurosawa is nervous, she either bites her lips, her fingernails, or her wrist.
- In the third act of the Mr. Bogus episode "Bogus Private Eye", Bogus and Kevin the family bulldog both do this while watching a detective movie on TV.
- My Little Pony: Friendship Is Magic:
- Rarity bites her hooves as well in "Secret of my Excess".
- "Magic Duel". While Twilight is testing a magic spell on some animals, Fluttershy goes into overprotective mother mode and bites her hooves for the duration of the test.
- In "Equestria Games", one pony is seen doing this during Spike's attempts to light the torch.
- Twilight does this briefly when Pinkie goes missing in "Party Pooped".
- Classic Disney Shorts:
- Taken Up to Eleven in the Spongebob Squarepants episode "Graveyard Shift". As he listens to a scary story, Spongebob goes from biting his nails to eating his own arms, which then grow back and are eaten again. He then goes to eating arms out of a bucket like popcorn.
- Spoofed in the Scooby-Doo, Where Are You! episode "Nowhere To Hyde", where Shaggy does this after Velma calls him out for being scared, but he's actually biting Scooby's nails.
- Scooby Doo has also rapid-fire bitten his own nails in the Scrappy Doo episodes.
- Used in one episode of The Magic School Bus when Arnold, as per usual, gets nervous about the Wacky Field Trip of the Week. Ms. Frizzle snarks:
"In accordance with federal regulations, we would like to remind you that this is a non-fingernail-biting flight."
- An episode of Garfield and Friends had Jon being a nail biter, to find out such habits turned off a potential employer.
- In Popeye the Sailor Meets Sindbad the Sailor, Olive bites her nails like a typewriter.
- In an episode of The Ren & Stimpy Show, Stimpy begins biting his nails excitingly when watching a commercial for a contest involving Muddy Mud Skipper. He keeps putting his hands further into his mouth until he's chewing on his arms.
- In an episode of The Fairly OddParents! news announcer Chet Ubetcha bites off his fingernails, his toenails, then grabs his cameraman's hand so he'll have more nails to bite.
- In the Looney Tunes short "Porky's Movie Mystery" when a series of burglaries occur in Hollywood various star of the time are interrogated including Frankenstein's Monster who rapidly bites his fingernails like a typewriter while being interrogated by a tiny police officer.
- In one of the 1980's episodes of ''The Jetsons" Judy Jetson does this hoping her father George doesn't embarrass her with his dancing at her party.
- Yumi does this in one episode of Hi Hi Puffy AmiYumi, both with her own nails, and with Kaz's.