1. To get any current work or job half done.

2. Someone who only finishes half their objective.
"This car has been half built, looks like we got a halfjack on our hands."

or

"Damn! He only finished half the fence! What a halfjack!"
by Thereyougo. April 3, 2010
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1. One who never goes more then halfway on anything

2. A boyfriend never planning a date and leaving all the work to his girlfriend and more commonly referred to as a jackass

3. One who has winterfresh on a daily basis and swallows


EX 1. Paul never planned anything with his girlfriend so he is a halfjack / jackass
EX 2. Paul likes to swallow winterfresh
by Grem Lochington January 26, 2008
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