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1.
see also mushroom bruise and mushroom tatoo. It is the mark on a woman(or man), after being whipped by an erect penis.
did you see the mark on her face?, that must've been a blue mushroom
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2.
The act of gripping an erect penis by the shaft right below the head and punching the penis until it is completely bruised.
I was with this guy last night and he totally wanted me to blue mushroom him!
by johnredcorn69! August 24, 2009
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