One who robs others in a lawless area, especially as part of a group.

An outlaw.

One who cheats others.

(military, aviation) An aircraft identified as an enemy, but distinct from "hostile" or "threat" in that it is not immediately to be engaged.

(sports, slang) A runner who covertly joins a race without having registered as a participant.

(transitive, intransitive) To rob, or steal from, in the manner of a bandit.