shwank

The act of masterbation whilst in the shower.
Shwank, shwanking.
Wanking in the shower

Tom: Hey Lewy, you look really refreshed today!
Lewy: Yeah man, just had a shwank, felt so good.
Will: Wtf is a shwank bro?
Lewy: When you have a wank in the shower!
Will: Mad!

by Larry O'Fresh June 02, 2011