the word lying but built different

Basically another word for lying. It can be used like no cap or you can say stop capping

it means your lying but in a different way

lying for no reason. like actually why would you say this

Originally, a kneecap. The phrase "bust a cap" originated in Northern Ireland several years before entering urban gangsta culture, and referred to the nonlethal (but fantastically painful and disabling) practice of firing a firearm at close range into the crook of the knee. The practice served, and in some areas continues to serve, primarily as an intimidation tactic, and the victim becomes a hobbling reminder of what happens to "the enemy."

refers to the ignition cap at the base of a cartridge for a firearm. "bust a cap" means break the cap by pulling the trigger, setting off the explosion that propels the bullet