Pre-Beer 

Drinking the cheap beer or wine at home or in your car in the parking lot to catch a buzz before buying the expensive booze at the club

Q: What time you wanna head out?

A: I dunno, lets Pre-Beer it around 8 pm

Pre-Beer by snausages333 October 22, 2006

prebeer 

Good quality craft beers made available at the beginning of a Beer Swap/Tasting for guests to enjoy before the official Tasting begins.

"We're still waiting for a few more people. Would you care for a prebeer in the meantime?"

prebeer by Hassan Ben Sober December 15, 2011