Top Definition
Any really lame "prank" that requires a disproportionate amount of energy to pull off, thus causing the person pulling the prank to be more inconvenienced than the intended victim.

Named after UFC fighter Josh Koscheck who, as coach of The Ultimate Fighter 12, pulled incredibly lame "pranks" such as parking two cars really close to rival coach Georges St. Pierre's car so that he had to squeeze to get in the car.
I replaced your whole milk with 2%! KOS'd!!
by SBoI2010 October 07, 2010

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