grumpadin 

A slang term used to describe someone who is grumpy (picture of a gremlin/goblin/troll comes to mind)

"I hate Dan, he is such a grumpadin."

grumpadin by your mom is here again November 5, 2008

grossie grumpkins

The anonymous old man - most likely suffering from some form of dementia - who takes a shit in the sink of public restrooms

Don't go into the bathroom, Bob. It looks like Grossie Grumpkins struck again.

grossie grumpkins by Betty Wagaman October 15, 2006

Grumpstink 

When a person throws themselves into a tantrum of such ferocious proportions that they inadvertently pass wind.

"Dude, Ashton went off the rails so bad last night that she pulled a grumpstink! My flat still hums of it."

Grumpstink by Prof. S May 4, 2010

Grumpaluncher 

Grumpalunching is the ancient art of using a 12 gauge pump action shotgun to dispatch your enemies quickly and efficiently. Grumpalunching can only be properly executed while being in an a rather grumpy mood. Grumpalunching can be used in a variety of different ways, i.e.:
Family fall outs
Video games
Generally being pissed off
During movies
Destroying mopples/Nipples
General F***ing around
To deal with a cheating partner
History of Grumpalunching

Originating from South America in 1895 Grumpalunching has become a normal part in human society, Grumpalunching is a simple way to deal with disputes and sort out family fall outs. Grumpalunching was a key part in the Vietnamese war it saved many Americans lives almost as much as the Nanosuit 2 Armour module, combined with the power of Grumpalunching (Marshall law) both of which saved over 2,00,000 American soldiers who live to this day. all thanks to the 12 gauge shotgun!
Why Grumpalunch?

Grumpalunching is a simple and easy way to deal with a army, a little brother, EVEN A CAT, Grumpalunching is the future of science and peace.
so what does the Woman Mopple have to do with it?

The woman Mopple has grown a resistance to Grumpalunch bolts therefore it requires 10 or more grumpalunch bolts to finally kill it!

Guy 1: Wow that guy sure is a grumpaluncher

Guy 2: Yeah he kill 28 people in the last hour

Grumpaluncher by The Loner Boobatio May 17, 2011

Grumping it

When you skip a tutorial in a video game, and get stuck or lost in something the tutorial taught. A reference to Arin (Egoraptor) of the youtube channel Game Grumps, who would always skip tutorials.

"Bro, you're grumping it! You shouldn't have skipped the tutorial."
"Ah, yeah, I grumped it."

Grumping it by queephlosion December 16, 2020

Grumping 

When a person grind/dry humps a person alive or dead

"Did you see tom and tracy grumping at jimmys party last night?" " dude I totally practiced grumping on my pillow last night."

Grumping by Og_grumper_69 August 1, 2017

Grumping 

The act of making an exaggerated frown in the shape of an upside down "U." Often used when someone is being ridiculed in a joking situation.

While grumping be sure to make your frown as curvy and unpleasant as possible

Grumping by mmoneh November 18, 2011