die, dice, n. 1. in general usage, a small cube marked on each face with from one to six spots and used, often in pairs, in various games and in gambling by being shaken and thrown to come to rest at random on a flat surface; pl. dice; from Middle English dee, Middle French . 2. in gamerese, a polyhedral object used to generate random, usu. numerical, results; in addition to the typical six-sided die, four-, eight-, ten-, twelve-, and twenty-sided varieties are often employed. See also polyhedral dice, percentile dice. [GJ1]

Addendum: As dice are generally the foundation of all RPGs, due to their status as random determinant for tests made during the game, gamers are by and large obsessed with them. In addition to large portion of gamer-ese that has to do about or involving dice, gamers will invent esoteric ways to "fix their luck" to make the dice roll better (see dice karma, dice trick and Penn Gillette's Law), fiddle about with them like an OCD monkey on meth (see die spinner), create or buy "cool-looking" or intricate holders specifically for their dice (see dice bag), and there have been numerous cases in which verbal and fights have broken out at cons or even at the common table because another gamer "touched my dice".
Addendum #2: Gamers will also brag about their dice collection, as many of them attempt to gather as many as possible. The phrase "you can never have too many dice" is often uttered by such hoarders.