To drink the contents of one's beverage. Used especially when alcohol is concerned. Literally to tilt the bottom of one's glass upward until it is empty.
The bar closes in 10 minutes. Bottoms up, gentlemen.
by Becky C March 14, 2008
1. Coitus a tergo, a sexual intercourse where a man is behind a woman, both kneeling. Also reffered to as doggy-style,dog-fashion.
While doing it bottoms-up she was moaning like crazy!
by necrotism May 21, 2006