Dungeon

dungeon, n., D&Dism 1. a dark usu. underground prison or vault; from Middle English donjon, from Middle French, from (assumed) Vulgar Latin domnion-, domnio "keep, mastery," from Latin dominus "lord." 2. (gamerese) in fantasy RPGs, the subterranean catacombs located beneath a castle. See dungeon crawl. 3. a generic term for the setting or module in which a fantasy RPG takes place (whether or not said setting actually contains a dungeon); synonymous with module. [GJ1]