look up any word, like fleek:
 
1.
To have to go number 2.
To poop.
To make naughty water.
Brennen had to go bust a grumpy, becuase he'd tried to move and built up enough bodily waste to kill an elephant.
by RevStan January 09, 2004
 
2.
The phrase "bust a grumpy" is used to refer to anything that is excreted through the anus, including both gas and feces. To properly bust a grumpy, one must abide by the following rules:
-Claim that he or she is going to "bust a grumpy"
-Excrete something (be it solid, liquid, or gas) from the anus.
Tom:"Dude, I'm gonna bust a grumpy!"
Walter:"Oh, no! Wait!"
Tom:*Farts*
Walter:"Oh, man! Everybody watch out, Tom's bustin' grumpies!"
by Losgunn February 04, 2008
 
3.
having to take a crap.
Dude, I have gotta bust a grumpy.
by bezel333 December 31, 2005
 
4.
Passing a large usually unwilling stool that is rocky hard and very large.
Joban: I gots to go bust a grumpy before i shit my pants.

Jovan: Make sure you dont miss the bowl again.
by A little hack magic July 05, 2010
 
5.
Most commonly used in reference to flatulence. Specifically refers to the act of expelling acutely pungent methane gas out of one's butt.
It was the combination of 3 large bean burritos, 2 Red Bulls and a large pickled ghost pepper that caused Jordan to bust a grumpy.
by Mr. Spicer May 24, 2014
 
6.
The act of farting extremely loudly and abruptly.
Damn bro did you just bust a grumpy? I can smell it all the way over here!
by Snowfakee May 31, 2012
 
7.
having an orgasm, especially when one has an angry-looking o-face
After getting 20 minutes of head, he would bust a grumpy all over her face
by kkit January 13, 2010