In beer pong, a cup which each team fills 3/4 of the way up, and then proceeds to place anywhere in their own rack. The opponents turn around when the cup is being placed so that they do not know which cup to shoot at. When during the game either team proceeds to hit their opponents' celebration cup, the team whose cup it is gets to celebrate because, as a result, they get to drink extra! A loud celebration ensues, with all four players taking part--two of them because they hit a cup, and two because they get to enjoy more delicious Natty Light. It is also common courtesy to thank the opposing team for hitting your celebration cup.
"Dude look, they just hit the celebration cup!" (screams of joy ensue)
by BTfuckinR February 18, 2011