Head Bump, Fist Pump 

1. The act of masturbating (the bumping of the tip of the penis) and fist pumping at the same time. This act is usually done when watching exciting porn or when someone just really likes Jersey Shore.

2. The act of making the previous definition motions as a dance.

1. Person X: Dude you wanna go down town tonight?
Person Y: Na I rented a gang bang porn and I think I'm going to cheer on the guys by doing the Head Bump, Fist Pump.

2. Person X: How are you banging a different girl every other week?
Person Y: I just Head Bump, Fist Pump like a champ at the clubs.

Head Bump, Fist Pump by C.2.P. June 24, 2010

bumper head 

1. A person who copies everything they see others doing.
2. A trend follower; someone lacking originality.
3. A biter.

I bought a Rolex. Two weeks later Jay went out and bought a watch just like mine. Damn bumper head.

bumper head by E. Richmond, III June 27, 2006

Back Bumper Head 

Back bumper head is when it hits the very back of the throat then the girl makes a soft and sweet gagging sound (It Creates more saliva)

Damn that girl suck a dick. She gave me back bumper head. I just about came down her throat.

Back Bumper Head by SadGuyStitch September 14, 2006

Bumped your head 

You thought wrong

(Very common in the California Prison System, & on the streets)

John can you loan me some money

You bumped your head, no way am I going to loan you any money.

Bumped your head by Kconnor56 July 1, 2010

have you bumped your head? 

It essentially means you have you lost your mind? or it can be used to express your hatred or dislike for a particular activity or person, similar to kms.

"Moe's is better than Chipotle."
"Have you bumped your head?!?"
or

"This traffic makes me want to bump my head."

or
"Help! I have bumped my head and I can't get up!"

have you bumped your head? by colls42 December 4, 2013

Fell and bumped your head 

Meaning you must be seriously crazy. That you or someone else is experencing a really dumb moment at that time.

After Jimmy made the dumbest comment I ever heard I said fool you done "fell and bumped your head"

Fell and bumped your head by darrin2000 November 29, 2007

did you bump yo head on a cabbage truck 

what u say to someone after they say something completly ridiculus or stupid

Lady- Baby, no more going to the strip clubs. its tearing us apart.

Man- did you bump yo head on a cabbage truck?

did you bump yo head on a cabbage truck by micheal watts January 9, 2008