Top definition
When playing in extreme sports or running. Or fucking for so long and hard that you begin to perspire on your derf. (space between your balls and asshole.)
Shit Sydney! You made me get derf sweat! But damn that pussy was good!
by tit fucker October 21, 2007
Mug icon

The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

Buy the shirt