A person who has exceptional skill at any particular online
multiplayer game, typically first-person shooters.
Originates from the Half-life mod,
Counter-Strike. Earlier versions of the game had serious security leaks, which were exploited by hackers, who created ways of infallibly winning every game. This practice was, of course, shunned by the remaining community, and the game's creators, Sierra, released patches to help prevent hacking. However, the terminology lingered on, so that someone who
inevitably won every game was still referred to as a 'hacker' or more favourably 'h4x0r'