1. General Motors, an automobile company.
2. "Game Master", one who runs, maintains, and/or referees an ongoing game (usually an RPG). Sometimes used to refer to the administrators of an MMORPG
3. The arbiter of a tabletop roleplaying game. A broader term than DM
or similar terms that are usually more specific to certain games.
1. I got my car at a GM dealership.
2. That stupid GM banned me from World of Warcraft
3. I think my D&D
group has the worst GM ever.