Term used to define the inabilty to stop grinding your teeth, chewing, licking your lips, or shaking/moving your jaw when high on uppers such as crack, cocaine, e, and crank. A negative effect of all uppers. Why ravers have binkies.
my friend and I did amphetamine and got terrible crack jaw we each chewed and entire pack of orbit that night to stop from fucking up our mouth.
by yoitsashlee February 12, 2007
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