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