bum knuckle

The lower part of the spine, the coccyx.

I slipped on the ice and landed on my bum knuckle.

by farther jack June 14, 2010

bum birth

The act of finally following through in the comfort of your bathroom following a long period of constipation. The feeling of joy mixed with a likely feeling of discomfort due to the build up of matter since the onset of constipation creates the strained feeling of childbirth from the rear. Usually followed by a feeling of weary elation that is once again similar to that feeling following the birth of ones child.

'I finally gave bumbirth today.'

by MollyGenevieve May 14, 2005

Up the Bum

when michael takes random people (e.g his father) up the bottom

by Anonymous April 1, 2003

Bum Cheese

When a gay man allows sperm to go hard in his ass

"I havent washed in like a week, i still got bum cheese in my gay ass"

by mark March 22, 2004

bum box

noun - a less expensive pack of cigarettes used by a smoker to give to a smoker who is out of cigarettes, so you won't have to give out of your precious more expensive higher quality pack of cigarettes

Oh! You cannot have one of my American Spirits, but you can have one out of my bum box of Basics.

by Wrestlemaniakla October 27, 2010

Thunder Bum

When one has a severe dose of Diarrhea

After eating a very spicy or hot meal which then results in you "Following Through" to the extreme you have a dose of "Thunder Bum"!

by Flattyflatdog October 9, 2011

Ya Bum

Something that you call your nephew in the middle of a no swag summer, cuz he's not living healthy. A term of endearment sometimes (rarely), other times you just a bum.

"This is not a wig it's a fresh ass cut, I watch anime with bae and peel potatoes for lunch. I got no swag on me I can't say it enough and if you come to me with swag I'm not saying too much…YA BUM." - from the #1 healthy living individual Caleon Fox.

by Pablo_21 October 5, 2016