A method of persuation or intimidation that originated from the I.R.A. (Irish Republican Army) where a person is held down and someone takes a 2x4 piece of wood with a nail stuck through it and beats the victims knees with it untill they rip his/her knee cap off or permanently damage it so they can never walk again and undergo serious pain and agony.
An Orange coat got knee capped to scare the british out of Ireland.
by MoFo'in CRIT January 23, 2005
The act of breaking someone's kneecaps to prevent movement.
I kneecapped your mother. With my penis.
by tardstroker May 26, 2010