Tri Party

n.

A mindblowing chaotic blockbuster event hosted by the three-headed party monster Omega Sigma Tau-Lambda Theta Delta-Gamma Epsilon Omega. One night and one night only is one able to witness such a tremendous phenomenon.

Can be used as a verb.
"What’re you doing tonight? Tri Partying? Nuts, man"

by Three Headed Party Monster November 1, 2005