A dumb person who just keeps getting dumber.

As heard on the Rush Limbaugh show, which gave a shout-out to Urban Dictionary regarding this word.
Ardent John Kerry supporters are a bunch of jackballs!
by Hyacinth Bucket December 31, 2005
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knucklehead, fool, dummy, idiot, moron; depending upon the context.

Jackball is word for which the meaning is subjective and entirely related to the user's state of mind. It ranges from the 'knucklehead' to the 'idiot' or 'moron' end of the scale depending upon whom you are referring.
Example: When addressing a friend it is more likely meant in the 'knucklehead' sense. If you were driving down the road and some manic cuts you off or you're watching TV and Bush is trying to complete a sentence or pronounce the name a of a foreign dignitary and you yell, "JACKBALL!" Clearly, it is being employed in the 'idiot' or 'moron' sense.
by Jackball Hansen March 21, 2006
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Can be used as a verb, meaning the deliberate act of taking or stealing. A jackball is a small "victory" for the jackballER and an annoyance to the jackballEE. It can often be advantageous for the jackballER to appear unaware of the jackball if noticed or confronted.
That lady jackballed my spot in line!

If this guy gets up, jackball his seat.
by n8dizzle November 22, 2006
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; verb. to get jackballed is to have a jack-in-the-box ball placed unwilling on your cars antenna more than likely the said jack ball was jacked from anothers' vehicle. thus acquired inappropriately
"What'd you do this weekend?"
"I went jackballing!"

"Dad! You totally jackballed me!"
by sup3r dup3r November 9, 2009
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Related to Jackball. To be in a state where you get so upset that you act dumber and dumber, further hurting your own cause.
The mob got jackballed up and continued to riot, when they realized that they were only helping the group they oppose.
by Brian A. Miller October 12, 2004
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