Second Life features two built-in maps: a world map which shows various information about the world, and a mini-map that shows all residents in range of your avatar.
The term map is also slang for when another resident teleports to your position (either from your profile or using an avatar scanner to locate you in the current sim you're in). Mapping someone without their permission is usually considered rude (and could be abusive).
A map can also be short for a texture map.