Stands for: Sexy Dance Party. A SDP can only occur if a minimum of two of the Original Three are present. Usually consists of loud music, crazy make-up, Jenga, All Dressed and Salt and Vinegar chips, wild hair, hottubing, and copious amounts of photography. Many of these pictures do not end up on facebook for obvious reasons.
Person one: I think it's time for another SDP.
Person two: Yes! What is this now? SDP8?