Quote Originally Posted by Raminax View Post
Aye. As far as I know, it's short for 'mobile (creature)' and actually referred to NPCs of all kinds that were capable of moving on their own, rather than only hostile NPCs. Can't remember which specific MUD coined the term, though.
More specifically it stands for "MObile OBject", it's a pretty old term as far as I can tell. Dunno which game/community it's originally from, either.