It is when you plow a chick sideways in the pooper while pinching her buttcheeks together and proclaiming your male dominance.
John gave Emily the Pittsburgh Pinch after the prom.

Tina said, Come here Tyrone and give me that old steamy Pittsburgh Pinch since you got me those nice cubic zirconia earrings.
by Broe Bersky June 14, 2007
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