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N. A knife, kukri, machete, dagger, or other short edged weapon of extraordinary size, value, or lethality. A weapon or weapon wielder that may cause drastic damage when used correctly. Most widely seen in video-games such as Call of Duty, Team Fortress Two, or Counter-Strike: Source.

V. To kill or obtain multiple or simultaneous kills with a melee weapon in a video-game.
John - "Hey man, wanna help me build an Eiffel tower with Kaylee?
George - "No way man, I've got a huge kill streak in Counter-Strike: Source right now with my überknife."

John - "Oh man, you just pulled off that sweet überknife there bro!"
by Uberknife October 07, 2011
To get on a knife only account on Call of Duty: Modern Warfare 2 and anger other players by talking trash and kill them with the knife on several occasions.
Lol, I just uberknifed that kid in the game winning killcam.
by tematamos July 24, 2010