A sideways ballsack. Primarily referring to a re-rack in beer pong, placing the last two cups vertically.
"Yo can we get a vertasack?"
"I'm about to drain this last ball of the vertasack, you figgadealz me?"
"I'm about to drain this last ball of the vertasack, you figgadealz me?"
by The Urban Fizz May 22, 2016