noun. 1.) The annual Nerdian last-hurrah of the school year; takes place on the first study day prior to finals (first day after the end of classes), where a giant one-shot RPG involving all of the resident RPG/Gaming-club members takes place. Often involves mass hysteria/confusion/craziness due the abnormally large amount of people involved (compared to typical RPGs, which involve smaller groups of 3-6 people), large amounts of caffeine and sugar, and more nerd-jokes than most "normies" could possibly handle. Typically takes place in a college/university setting, but may take place amongst high-school students as well.
Person 1: "Hey, what time is Nerdpocalypse tonight?"
Person 2: "Try to be there around a quarter-til; don't forget your character sheet and bring a handful of D6s if you have 'em."