hipsterのようなどんな単語でも探してください。
 
1.
To un-intentionally show you bum. Usually only the top part is revealed when bending down. Or if you’re a builder of some description you will already be wearing loosely fitting pants that assist in revealing your bum crack.
I was walking along the street when I saw two moons looking at me. The fattest builder was showing every one his bum crack. To which I shouted out say no to crack!
Harpoによって 2004年07月20日(火)
 
2.
An inch long crevice found on the derriere, that has escaped the modest covering from trousers.
"Cor, look at her bumcrack, the dirty slapper! You could park a car in that!"
BumcrackTheDogによって 2004年11月02日(火)
 
3.
Completely pointless person, thing or action. Something that offers no value for its existence.
Your goatee is a bumcrack.

That bumcrack professor barely teaches us anything in class.
Food fiendsによって 2010年12月05日(日)