Definitions by Joe Fagan

imma pop a cap in yo ass 

An Agressive Slang, meaning the user is going to shoot someone

50cent "yo biatch! fuck yo nigga ass!"
DmX " Yo imma pop a cap in yo ass"
Joe Fagan "Damn, Thats Wack

imma pop a cap in yo ass by Joe Fagan February 18, 2004