To pregame or drink before you begin your night out on the town. To consume alcoholic drinks at one's home, perhaps due to: a rough economy with hard times, being an underage child without a fake ID, or in most cases, insurance for good times.
Me: "We're going to a speed dating event tonight???"
John: "Yep at 10pm"
Me: "Wanna come over and fill up your tank at 8?! I'm gonna need it!"