From HomoExcelsior

/muhd/ n. [acronym, Multi-User Dungeon; alt. Multi-User Dimension] 1. A class of virtual reality experiments accessible via the Internet. These are real-time chat forums with structure; they have multiple 'locations' like an adventure game, and may include combat, traps, puzzles, magic, a simple economic system, and the capability for characters to build more structure onto the database that represents the existing world. 2. vi. To play a MUD. The acronym MUD is often lowercased and/or verbed; thus, one may speak of `going mudding', etc.

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