Mid 90s urban culture terminology for defeating another person in any sort of competition, whether it be gaming, boxing, killing, etc.
N.W.A. Song "Straight Outta Compton" -

"Me and you can go toe to toe, no maybe

I'm knockin' niggaz out the box daily"

Ex. 2-

Man, I can kill you at Mortal Kombat II.

Oh yeah, I'll knock you out the box, bitch!
by gregatron5000 June 28, 2009
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