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1. (adj.) - generally bad; "gup" could apply to a person, action, object, situation, condition, etc.
2. (n.) - a person who might be considered rude, malicious, or unpleasant in any way.
3. (v.) - to go out of one's way to make another's life worse; to bother, taunt, bully, disrupt, provoke, etc.
- to let someone down or fail to meet certain expectations of oneself
4. (int.) - an exclamation of disapproval or discontent

Variations of "gup" include:
- gupped: having been screwed over by a person or an incident
- gup outta here: a phrase (slang) used by the speaker to indicate that he/she no longer enjoys or tolerates the presence of another individual or group and would be happier if the unwanted individual or group left the scene.
- gup that: a command/exclamation, simply meaning "hell no"

see also guppy
1. Aw man dude, we're out of funky juice... That's gup.
2. Dude, Billy stole my ball. The kid is such a gup.
3. Don't invite Joey... He's always guppin dude, I can't stand him.
4. *flat tire* GUP.
5. Joey: "Hey man, you wanna come to my ballet recital?"
Liam: "Nah gup that dude..."
6. You heard about Nate dude? He bought a loaf of challah for $5.49 at Whole Foods, and they only cost $3.29 at Panera. He got gupped hard.
by Buffalo Jones May 20, 2013
G up is similair to the phrase "fire it up" It refers to becoming prepared; to bring your A game; or go balls to the wall.
As heard by Theo on MTV battle of the sexes: " Come on Robin, G up baby!"
by Max Wittler January 25, 2005
having large wings
The eagle will need gup to fight a storm
by seabird21 April 09, 2013
noun - The college freshman who took his high school girlfriend to prom; little does he know that she's going to be more run through than the autobahn once she enters college herself. Cousin of the classic beta male.
Example 1:
"that guy that came into our store with his high school prom date was the epitome of gup!"

Example 2:
Employee 1 - What kid brings their high school girlfriend to a casino after prom for ice cream?!
Employee 2- A straight gup, that's who!
To make someone feel bigger, better, than they really are.

To lie and shmooze someone in order to take advantage of them.
Sometimes you gotta G up people to get your slice of the pie.

Yo that chick g'd you up for a free drink on your tab, sucka.
by Ragingclown September 20, 2013
A term used commonly in London to describe the action of being snitched on by somebody, to the police. Short for Grassed On.

"Gee'd up"
"G up"
Bubba1: "I can't believe that pussy G'd you up."

Bubba2: "I'm gonna jook him when I finish my bird!"
by Liquifux August 05, 2004
Short for "green up"; the act of signaling readiness to play in the lobby of the online PS2 game Socom 2.
Impatient PS2 Nerd: What the hell is taking so long? G up already!
by Jeff Foxworthy June 26, 2004