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

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