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Game Mastering (in a roleplaying game). Aka DMing (Dungeon Mastering)
I've been GMing GURPS for the past few years.
We need a new D&D Dungeon Master here, but they are all GMing other games.
by Calliban March 12, 2009
Using gmail's instant message/chat script.
I was gming him all day since I couldn't download aim on the public computer.
by dapaintballer331 April 16, 2006