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1. high gear
to be high while driving.
Josh: dude let me drive

beck: no dude why?

Josh: your driving in high gear!
2. high gear
the premptive idea, or state of mind to succeed at sexual interaction with the opposite sex. This state tends to produce the most desparate attempts at sex, with the most hilarious outcomes.
Dan was such high gear last night, he did a fatty.
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