1 definition by Global Aneurysm

Noun-The bruise left after a man takes his penis and slaps his partner across the head.

Verb- The act of giving someone a mushroom cap.
Noun- Last night I left a huge mushroom cap on my girl's face.
Verb- I am going to mushroom cap you with my dick!
by Global Aneurysm January 17, 2012
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