Grundle is another word for chad: the region between the balls and the arse-hole; can be an erogenous zone for some.

Girl: I was fingering that part between his balls and his arse and there was shit there.
Everyone listening remained silent but later laughed among themselves:
'Eww! He had a shitty chad.'

When you measure your dick, you don't start at the arse-hole and include the chad; you risk getting shit on your measuring tape.
Q: What on earth is a grundle?
A: You know, the chad, the part between balls and arse.
by Chane. March 28, 2020
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The act of burrowing your nose into someones anus durring sexual playtime. A gluteal motor boat. Also known as a "Steam Boat Willy".
We started with the Dutch rudder, then moved on to the Dirty Sanchez, and ended with a lengthy and lively Grundle.
by Tasty time May 21, 2012
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noun: The sweat off your balls.
The guitar picks stink of Dave's grundle and tiger balm!
by Metal Maniac February 27, 2006
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The trashiest excrements of trailer park septic tanks, which, when mixed with crack-cocaine form into an American of sub-average intelligence, and are of the lowest societal and economic standing possible, ever.
Is that grundle pregnant, again? Shoot, it looks like her dad forgot to wear a condom, again.
by greedy grundle groper February 22, 2010
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A noun used to define the sticky build up found underneath the scrotum. Build up increases when the persons doesn't shower or has had hot sweaty day.
Person 1: Yo J-Kwon, take a wiff of this.
Person 2: Damn! What the hell is that on your fingers.
Person 1: I haven't showered in days, and that's some of my wicked bad grundle build up from my fat ball sack.
by Flo$$y B June 1, 2005
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The simultaneous occurance of every humanly imagineable bodily function (i.e. ejaculation, weeping, defecation, urination, hemorrhaging, perspiration, sneezing, coughing, drooling), resulting in both severe pain and unparalleled pleasure.
In loving memory of Jacob Anthony McCormick, who deceased this past Monday, December the 6th, 2005 from an unexcpected, fatal grundle. God rest his tormented soul and mutilated body.
by Jordan Henry and Mark Dover December 6, 2005
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A large quantity of something awesome, can also be used as a measurement of some thing awesome.
There are a grundle of tattoos on that man's foreskin.

That chip is going to make you car a grundle load faster.
by bamf bromine April 6, 2011
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