look up any word, like cleveland steamer:
 
1.
A Pump Like Instrument, That Is Used For Clearing Out Ones Rectum, Prior To Anal Sex.
John: Ima Do Her In The Arse Later.......

Tom: Make Sure She Bum Pumps First, Otherwise, She Will, Without A Doubt, Dirty On Your Cock Stick...
by Buperter August 06, 2011
 
2.
To inflate a woman's anal canal by pumping one's phallus in and out. The air pressure created by the pumping will result in a massive expulsion of the air once the phallus is removed.

The expelled air often has a minty aroma and tastes mildly sweet.
1. I bumpumped her and the sweet essence of heaven was emitted.

2. She was bumpumping me while i bumpumped the hell out of the girl in front.
by KorrrrrrnHuska December 14, 2009