1 definition by Joe Timewaster

To fire a gun, usually at someone.

Refers to the fact that guns fire when the trigger is pulled and causes a firing pin to literally "pop" an explosive cap attached to the end of a bullet, causing the bullet to spiral out of the grooved barrel at tremendous speed.
The rap artist stated that he would pop a cap into another rap artist, but we all know that the state would never grant him a concealed carry license due to his convictions for multiple felonies, so he'll have to purchase a firearm through the black market.
by Joe Timewaster April 15, 2007
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