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When a person repeatedly thrusts the gas pump in and out of his car, trying to get every last drop of gasoline out of the hose and into the car.
...One day, perhaps two or three years from now, gas prices will get so high that at gas stations everywhere customers will be gas humping so much that they'll need to create all-steel pumps to prevent breaking of the pumps.

"I went to the gas station the other day and saw this perverted old man around 70 who looked like he was trying to screw his big Cadillac Deville. Upon closer inspection I saw he was just gas humping."
by Adel7 December 16, 2007
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