In sports, when an athlete has a superlative (if he is a star) or uncharacteristically good (if he is a lesser/role player) performance. Usually applied to fantasy teams, but can be used in a general sense as well.
Synonym- blow up
Antonym- ho' out
1. The Star
Fantasy Football Player 1 (mimicking Denzel): "King Kong ain't got nothin on me!"
FFP2: "Get outta here man, I would have beaten you by at least 10 points if Adrian Peterson hadn't showed out with over 300 yards."
2. The Role Player
Fantasy Basketball Player 1: "What are you talking about, Eric Dampier gets 20 points, 10 boards, and 5 blocks all the time"
FBP2: "Quit lyin to yourself. Those numbers are Erica's biggest showout in like 10 years"
3. The Non- Fantasy Player
Stephen Curry baby--puttin Davidson on his back with a 40 point show out. How you like them apples??
4. Famous Usage
Brendan Haywood, center for the Washington Wizards, screaming in the face of 20-year-old Andray Blatche in the pregame introductions of one of Blatche's first starts:
"Show out or Ho' out!"
1. To show up at a party/location when it is among many options for that night.
2. Alternate/Less Played out way of saying roll up.
guy: Where are you and that cute roomie of yours gonna be tonight?
girl: Oh, I think we're gonna be at Morgan's bday party--it's her 21st so we're all gonna be rowdy. You wanna come, it's at Old Glory?
guy: Drunk hotties? Yeah I'll definitely show out for that.
To act out of character usually to get attention or because one is upset.
"You see me party with some other bitch, and you wanna show out" 50 Cent-After My Chedda
similar to show off, but usually meaning a failed attempt to impress others.
"Yo, check out my rag chevy! Man, you just showing out."