A Team-Killing Fucktard is commonly encountered in online team-based games, such as Halo (where the term originted).

Normally they are Noobs or Newbs, or just Fucktards in general.

Team-Killing Fucktard can be abbreviated to TKFT. Plural version of the noun is TKFTs. It can also be used as an adjective to describe someone who has killed a team member. There are two definitions of such team-killers,
True Team-Killing Fucktards (TTKFT) and Enraged Team-Killing Fucktards, also known as RageQuit TKFTs (RTKFT or RQTKFT)

Origin:
The origin of the Team-Killing Fucktard originated from popular Halo webseries, Red Vs Blue (RVB) it can also be said that the first recognized TKFT is Caboose from the series, for killing team-captain Church with a tank in the first season. Caboose may not be the first TKFT, but the famous incident has sparked awareness of the dangers that TKFTs present to the online-gaming community and beyond.
You shot Church, you Team-Killing Fucktard!
by Super-Ultimate-Ownage-Penguin September 11, 2011
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One who kills (either accidentally or purposefully) a member of his or her own team. Someone who should be killed themself. often used after a lasertag game with friends, during a counterstrike or halo game, or any of the other FPS or gun-related team games.
Damnit, you team killing fucktard, Watch where you're shooting!

You fucking killed me, Team Killing Fucktard!
by Aadon Gondahlvor February 10, 2004
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Somebody who kills a member of his halo team out of boredom or accidentalities
You shot church you team killing fucktard!
by Yaren October 1, 2004
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when u kill ur cohorts, team mate, or distraction. AKA, caboose from Red vs. blue
Tucker: You killed Church you team killing fucktard!!!
by gunslingergirlvy_c_e August 9, 2005
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Caboose from Red Vs. Blue. go to www.redvsblue.com
After Caboose shot Church(a teammate), Tucker called him a team killing fucktard
by Taylor March 5, 2005
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a jagoff who steals their friends lady friend rite out from under them. this smelly goat should have a cock shoved up his butthole as punishment for his douchebaggery.
josh- john how is sam
john- idk i think cdick stole her from me
josh- whoa, what a team killing fucktard
john- ya, pretty much
by cdick May 9, 2008
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this is the second definition of the Team-Killing Fucktard also known as the TKFT. the plural form of TKFT is TKFTs.
Definition 1 of TKFT is the True Team-Killing Fucktard. if you are confused on which definition is which, be sure to check out that page, too.

2. Rage-Case TKFT (or Rage-Quit TKFT):

This version of the TKFT is MUCH harder to detect. they are ninjas, assassins and spies. in the world of online games, they are steriotypically pissed-off asshole ten-year-olds about to Ragequit; they tend to talk in the n00b language and are usually almost completely fluent in said language. unlike the True TKFTs, who simply dont know how to play.

Detection:
Early detection is not always possible. Much of the time, this breed of TKFT will go unnoticed in a crowd or teammates, blending in perfectly. The exceptions occur when they make their presence known, often by lapsing into noobish. The known detection methods involve checking for anger and hostility towards other teammates, reviewing the player's dialect to determine if they are a troll, n00b or TTKFT, and by watching for reckless playing manner with heavy weapons.

Prevention:

Unfortunately, this Rage-blinded TKFT cannot be fully prevented. Sometimes, they call for a specific action, such as being expelled from the game or team-killed into RageQuitting. the players who TK or kick this type of TKFT can be referred to (comically) as TKPS or Team-Killing Problem-Solvers.
Note: "Ragequit team-killing fucktard" just announces what breed of TKFT they are. you may mix it up as you wish. some common acronyms are RQTKFT, and RTKFT.

p1: U d1rTy M0Th3rFuCk3r!!! Ur M0M h@d N0 cUmPl@nT$ L@$T n1GhT!!!!! HAHA L0L0L pL0X!!!
p2: Dude, its just a game. what's your problem
p1: 1m M@D @ U D:<
*P1 kills p2 then ragequits*
p3: hahaha! he did such a ragequit. what a Team-Killing Fucktard!!!!!
p2 as he respawns: tell me about it.
by Super-Ultimate-Ownage-Penguin September 11, 2011
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