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A lude gesture involving the extension of the third finger on the left hand out the window of a moving vehicle. While this gesture is most often reserved for the operator of the vehicle, passengers in the front and rear may be recruited as needed. ie. flying the bird as an excuse for driving like a masshole.
Jonny flashed his Boston turn signal as he cut off all the oncoming traffic.
by goldennutsachs July 14, 2012
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