Refers to someone rediculously immature,stupid,or just plain out retarted.
Dude we went to chruch with my girlfriend and my brother was acting like a total "crackJack",I was totally ruined.
by mxxx July 11, 2008

6 Words Related to CrackJack

a word meaning okay;also used for crackhead
maya:do you wanna go to the mall?
by maya April 04, 2003

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