ass pumping 

ass pumping - utilization of the buttocks in a general up and down motion to facilitate the use of a pump or other similar applied pressure working device. Definition may be inclusive of fully or partially clothed buttocks, or entirely unclothed buttocks.

Common devices used when ass pumping:
tire pump, beer keg "tap"

Expressions: "You can pump a keg with that ass!"

ass pumping by TCR May 22, 2006

Madden Ass Pumping 

The act of melting down a Madden CD and placing it into a syringe then injecting the hot liquid into one's ass like a steroid injection.

Adam melted Madden for Eric because the game was so garbage. Then Eric bent over and got an injection of Madden. This is Madden Ass Pumping.

Madden Ass Pumping by AFNLD December 16, 2010

pumping ass 

anal sex

Person 1: Hey, did you hear what Jason did the other day?
Person 2: No, what'd he do?
Person 1: He was totally pumping ass with Becky.
Person 2 : Goals.

pumping ass by lolingatyouandyourlife June 20, 2015

Pumping Ass 

Moving your ass whether it be at work, home or even in church

Me: Hey Sharon how are you today?

Sharon: FUCKING AWESOME, I'VE BEEN PUMPING ASS ALL MORNING!

Me: ummm... that's good..

Pumping Ass by Marks920 July 22, 2016

pumpin that ass 

When a nigga sees a nice ass, aint nothin goin through his head but pumpin that ass, just straight hoppin up n down on that shit.

ay yo this is my crib, get me a girl up n here and u kno i be pumpin that ass.

pumpin that ass by akjohnny February 23, 2009

assumping 

Ass Humping, usually in a vigorous manor.

John really enjoyed the assumping he got the other day

assumping by Butt Pirate 23 February 13, 2012