The Brief: To pregame means to get drunk before going to a social event.
“Pregame” or “pre-game” can also be the name for a get-together or kickback in which a few people gather to drink alcohol before going out to a party, bar, concert, club, or game.
The term pregaming is common in college party culture. Students will often pregame before a party or sporting event.
— alex boten (@codeboten) March 16, 2019
Pregaming is usually used as a way to save money on drinks or to skirt rules against underage drinking. It can be a form of binge drinking, especially if people are trying to get drunk quickly or if they drink at both the pregame and the actual event, and can actually lead to blacking out.
— Mary (@mtkr) March 18, 2019