gu 

an expression of suprise

GUU, thats expensive~!

gu by Nate quick December 28, 2005

gu 

Giggling uncontrollably-used because it is shorter than lmao, and more expressive than lol.

A: *Says something hilarious*
C: gu!

gu by Fruitloop January 9, 2005

gu 

When your stupid ass friend hits the keyboard as you are trying to chat in an online video game, but all he manages to get are the keys gu.

"hey man which way next?"

"gu"

gu by Ddog August 8, 2003

Gu 

East coast slang for an annoying pest who no matter how much you try and get rid of, persists and continues to annoy. Usually every "clique" or friend group has one and although they put on an act while around the "gu"; they ignore him/her at all costs and joke about how much of a "gu" that person is. In addition to having no friends, the "gu" is the epitimy of grossness and therefore has zero game with the ladies.

Man did you see that guy walking with that group of people. Ya he was such a gu.

Gu by Departed33 February 21, 2010

gu 

An extremely leet counter-strike player. Guru.

I am a gu at that game.

gu by Mike March 2, 2005

gu 

A situation where things doesn't go as planned

you got lost in the woods

"man we are so Gued"

gu by Mutha October 3, 2003

gu 

gu, gued, guing..
adjective: hustled, shaded, had, taken advantage of, criticized, made fun of, heckled, laughed at.

"Eh man, he ran off with my girl and gave me the finger."
"Heh, you've been gued."

gu by Joey August 8, 2003