So you have a female character who lacks the characteristics and mannerisms of a normal female and only have the characteristics of a male. They can fight, then can play sports, they drink a lot, they play video games, and they're well-liked by the guys (at least some of them). Yes, that's a tomboy. But there's something missing. What could it be?
Well, all she needs is a trademark baseball cap.
This is the trope where a tomboy can be identified by wearing a baseball cap. Most of them wear caps if they commonly love to play baseball. They may wear it when they're in the army. Others wear it just for the sake of setting themselves apart from the Girly Girls she's expected to hang out with. As far as this trope is concerned, a baseball cap is like the cherry on top for the tomboy, and when tomboys wear caps, it's usually a cool sight to see.
They often wear their caps frontwards, especially if their hairstyle is a ponytail. They often wear their caps backwards just to make them look more of a badass. They even wear caps sideways if they're acting like the guys from the 'hood.
- Allie from Digimon Legend always wears a yellow baseball cap backwards. Plus, she's an Action Girl who does have moments of being a bit pragmatic.
- Jade Tanner from Supernannya: Pokémon AU, a black Pokémon trainer, wears her black/green baseball cap which matches the rest of her entire wardrobe on her green hair, backwards. Likewise, she would also have the trope of Characteristic Clothing Colors, alongside the trope of Action Girl, as in Pokémon battles, she kept scoring perfect battles, and took down Alessandro Todaro.
- Short Stuff from Daring Do can never be seen as an annoying sidekick to Daring Do without her trademark baseball cap. Despite this, she knows how to be a fierce fighter.
- The movie version of Lex Murphy from Jurassic Park is a tomboy who wears a baseball cap, although she's more of a computer nerd. In the books, however, she is a huge baseball fan and she does wear her hat proudly.
- Sam Montgomery from A Cinderella Story wears a baseball cap since she likes playing baseball. This is what makes Fiona to consider her unattractive despite being jealous of her.
- In a couple of scenes from She's the Man, Viola, a tomboy, wears a baseball cap with a British flag logo and has a huge interest in playing soccer.
- Amanda Lemmon from It Takes Two is an orphan tomboy who always wear baseball caps and loves playing street ball and hates acting lady-like for adoption.
- Dr Brown's daughter Delia in Everwood frequently wears a baseball cap and is very tomboyish. For instance, she plays ice-hockey in boys' team and she's very good.
- As opposed to her original portrayal as the the smart and sensible girl who enjoys dolls, celebrity gossip, and other traditional feminine activities, Alicia Guzmán of Carrusel is a tomboy who wears a baseball cap and likes playing football.
- Two of a Kind: Mary-Kate, the tomboy of the two, often wears baseball caps.
- Step by Step: Al, Frank's daughter, is the only one of the girls who is a tom-boy as her step sisters Dana and Karen are girly girls (identified as the smart one and the pretty one). Al often spots a baseball cap when she's younger on the show. She's into sports, outdoor stuff or she loves helping Frank with his work.
- Tony's daughter Sam(antha) on Who's the Boss?. Sam wears baseball caps during the first season.
- Telly from Salute Your Shorts occasionally wears one. Justified since she actually plays baseball.
- The Suite Life of Zack and Cody resident tomboy Max is introduced wearing a baseball cap.
- In the music video for legendary singer Kelly Clarkson's mid-2000s decade song Breakaway, a young girl with an aqua hoodie was wearing a black baseball cap backwards.
- Inverted in Peanuts, where the very girly Frieda refuses to wear a baseball cap even when she is playing baseball! She doesn't want to mess up her "naturally curly hair".
- Also inverted in a storyline where Marcie keeps demanding caps for their baseball team while Peppermint Patty, despite being a tomboy, a Passionate Sports Girl and captain of the team, argues that they don't really need them.
- There are a lot of pictures of British singer Ellie Goulding wearing a baseball cap backwards.
- Former WWE Diva Ashley Massaro wore a backwards black cap in her debut in 2005 (she also won the 2005 Diva Search). She stopped wearing it in around her return in 2008.
- Nikki Bella adopted this image after her 2013 HeelFace Turn. Coupled with wrestling in a t-shirt and soccer socks, it helps provide a Tomboy and Girly Girl dynamic next to her sister Brie.
- Liv Morgan is a Tomboy with a Girly Streak from New Jersey and the image is topped off by her wearing a baseball cap to the ring.
- In Disgaea 4: A Promise Unforgotten, Fuka wears a Prinny hat and happens to wield an axe in battle.
- In Borderlands 2, Gaige the Mecromancer (a Wrench Wench and self described "Woman of science and asskickery") has two heads which are caps of some sort; Keeping It Real (an actual baseball cap) and Read All About It (a paperboy style cap).
- Clementine from The Walking Dead was given a baseball cap as a gift from her dad. She also prefers playing around in her treehouse more than watching television and playing with dolls.
- Scooter is a playable character in flash games of Papa's Donuteria, Papa Louie 2: When Burgers Attack!, and Papa Louie 3: When Sundaes Attack!. She has appeared in every Papa Louie game after Papa's Pancakeria. She has a baseball cap, she wears it backwards.
- On Family Guy when the Griffins temporarily move to the south Chris becomes "friends" with a "boy" who turns out to be a tomboy wearing a baseball cap covering her long hair.
- An aversion in Recess where Spinelli, although she is a tomboy, wears a ski cap rather than a baseball hat.
- In one episode of The Grim Adventures of Billy & Mandy, Mandy invokes this by sporting a baseball cap as well as disguising herself as a boy named "Manfred" in her plan to prove to Billy that girls can surely play sports.
- From Arthur, there was a young female character named "W.D." who wears a baseball hat which goes along well with her boyish clothing, gender neutral haircut, and a gender neutral voice.
- Linny from Wonder Pets wears a trademark orange baseball cap and is a female, which often has the audience confused whether Linny was male, considering that caps are usually what males usually wear.
- Mike Mazinsky from Mike, Lu & Og doesn't usually wear a baseball cap, but she does don one in "Sultans of Swat" and "The Mother of All Marathons".
- Lor from The Weekenders sometimes sports one.
- The Loud House: Lana Loud always wears a red baseball cap, backwards.