CAP 

That's a fuckin' lie

Sam: I'm fuckin ballin
John: STOP THE FUHKIN CAP

CAP by Fatnoob360 September 1, 2021

cap 

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

"back off befo i cap yo ass!"

cap by bjg March 9, 2003

Cap 

Term used for the cap of a mushroom, usually one of the psychedelic nature.

"I ate a stem and three caps."

Cap by Sledulous June 29, 2009

Cap 

A person,who always tells such obvious things that people around think he is really stupid.
Caps are usually ridiculed.

-If you drown now,you will not swim any more!
-Thanks,cap...

Cap by As_you_want August 17, 2011

Cap 

A slang term commonly used by members of Gen-Z to say that something is a lie. Similar to its variation “capping”, which is used to direct at another person who is a liar.

Person 1: Mom! Nick ate my ice cream!
Nick: That’s cap!

Variated:

Teacher: Jack, are you sure your dog ate your homework?
Jack: Yes!
Bob: You’re capping, Jack! I saw you throw it in the recycling bin yesterday!

Cap by ChickenScrxtch82 January 3, 2021

cap 

insulting someone in a playful manner

Dude, I cannot believe you got capped on by a middle schooler. He burned you.

cap by zilenzer October 7, 2008

cap 

In Cleveland, 9 times out of ten it means to lie, front or bullshit. In noun form, a liar, or bullshitter.

Girl 1: I went to the mall and this dude gave me a discount on my Forces cuz I told him he was cute.

Girl 2: You cappin'!

- - - - - - - - -

Boy 1: Last Saturday, I got pussy from 3 different girls.

Boy 2: Man, youse a cap.

cap by AUTOPSY January 12, 2007