n. To drink before going to a party. This most often happens because they party where you are going to will be carding and you are under or because you want to drink something hard to start your night off. Often pregaming happens at the house and involves taking shots.
v. The act of partaking in a pregame.
1) We really need to pregame tonight before we go out.
2) I really pregamed heavily last night. I feel really sick now.