Someone who intentionally attacks his own players in an online game.

Teamkilling in games originated by people exploiting game servers that accepted 'friendly fire'.

More recently, celebrity gaming figures like LOLMAN have utilised impact circles of weapons so as to become profficient at teamkilling, even without 'friendly fire' enabled. In games like Unreal Tournament, this works by firing a projectile in the right place, so that the force of impact makes a teammate fly so far that he loses a frag due to fall damage. This is a 'teamkill'.
Some guy is teamkilling, he must be banned.
LOLMAN, stop teamkilling!
by GamerX March 13, 2004
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The killing of one's own teammates through one of three circumstances:

a) Lack of skill and shooting them accidentally, causing either death by fire or falling

b) Deliberately as an act of malice and/or general stupidity

c) Deliberately as an education to the killee regarding their own antisocial behaviour, a punishment meted out by skilled players such as LOLMAN
Ha Ha.... LOLMAN teamkilled that spawncamping n00b
by Carrot March 14, 2004
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In a FPS videogame (like Call of Duty), someone who kills people on his own team.

I do it in Call of Duty often (how do you think i chose this name?), it really rocks to see people get so pissed off.
Some tips on teamkilling in Call of Duty:

-Always use SMG's or AR's, Rifles are rarley useful in TK'ing, since you are almost always in close proximity.

-In Team Deathmatch mode, when you spawn, back up a few steps and wait. Your TM's should spawn very soon, and you can kill them as they appear. This pisses them off beyond belief.

-FORGE ALLIANCES!!!! If there's another teamkiller on, make sure you ally yourself with him and say on the same team, killing all other TM's and sparing each other.

-Never, ever teamkill with admins on, it's a very nice way to get perma-banned. Make sure you do it when only peons are in the server

-There's also another little strategy I use. (Team wounding) Use an SMG, and shoot your TM's in the legs, enough to ALMOST kill them, but not quite. This way, there's no proof, and they might kill you and then get banned!

Happy Team-hunting!
by Rampant Teamkiller July 04, 2004
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When a n00b is really crap at a game and they keep getting owned they'll kill their own team mates as its the only way to score any kills. More often than not they'll eventually get kicked from the server and everyone will remember how much of a twat they are.
cloudstrife :: heh lol im killnig u cos i am teh smatr
someone :: quick cloudstrife is TKing again, someone kick him
cloudstrife :: lol
PluCh :: PluCh to the rescue !!!
cloudstrife was kicked
PluCh :: FNAR !!!
by PluCh December 14, 2004
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One who intentionally disposes of the more useless players on their team in an online game, leaving only the cream of the crop behind.
Man, that guy's teamkilling us. He should be worshipped!
by Tano Pirrone November 18, 2003
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The act of killing players on the same team in a game which allows friendly fire. Teamkilling can be intentional or accidental. If it is done intentionally, it's usually out of frustration, boredom, revenge, or to get something that person has.

It is also a form of griefing, and is looked down upon by those who play the game normally.
OMG WTF HOW COME U KEEP TEAMKILLING ME OMG WTF!!!!!!!!1!1!!!11eleven vote him out!!!!1 this D00d is a gay hax0r!
by Rezel July 25, 2008
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What I spend 95% of my time doing on Call of Duty 4.

Best team killing class in COD4:
RPG
Sonic Boom
Martyrdom
This assholes teamkilling. Everybody file a complaint and get him kicked off xbox live.
by Evil Monkey 03 November 04, 2008
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