head jacks 

when one of your boys is getting a blow job in a car by a woman.

when somebody gets head jacks from that chilly chick.

head jacks by Spankey7289 August 3, 2008

Head Jacks 

Giving Oral Sex to Male from Female or Receiving Oral Sex from Female to Male..(Female giving to Male) In other words getting some Dome or Head or Brain.

Man, last night I picked up this chick at the Bar and took her to my car and she gave me Head Jacks.

The other day my ol' lady gave me some Chilly Head Jacks!

Head Jacks by Bryan13 August 1, 2008

jacks head 

a simile to refer to a large object

the size of the mountain i climbed it was almost the size of jacks head!

jacks head by tonto ya mad daftyz July 22, 2010

big head jackson 

the new twenty dollar bill

Aaron: Dude, how much did that t-shirt cost you?
Tim: I dropped a big head jackson on it.
Aaron: That's not worth a big head jackson.

big head jackson by Joe McC. August 22, 2009

Jack Head 

Can be of male or female gender.

One who thinks he/she is super great and attractive and must be idolized. Very selfish. Their head is so humongous that it cannot fit through a doorway. Comes on suddenly. Usually induced by alcohol. Includes a jumbo full teeth smile that is very phony. Lives a lifestyle which includes champagne wishes and caviar dreams on a beer budget. Always overshadows their mate. Is often seen as a family trait.

Can also be a verb: jackheadness

OMG look at that guy that thinks he is so great, he has his Jack Head on

My husband is being a Jack Head

He was talking to that girl with his jackheadness

Jack Head by StacySuperBoxWorker June 29, 2011

headjack 

in football when a player if facemasked, and his head is trusted backwards.

commentator 1: "did you see that face mask?!"
Commentator 2: "yeah, it was a total headjack - he could have got whiplash"

headjack by Lauren December 28, 2005