Gamers lingo, almost always refering to FPS (first person shooter) games. Killwhore can have several meanings, all derogatory:
1. A term used by a player who is sick of dieing to one player.
2. A hateful word used towards people who play the game the way it was ment to be played and playing well.
3. Somone who defies direct orders the commander / team leader just so he or she can scrape up a kill or two before they die.
I'm sick of those killwhores that bring the Rocket Launcher indoors! Thats leik, soooo n00b!
You Killwore! The SL said to pull back!