1 definition by *Dirty Dave*

When you're hitting a chick back door and you pull out a poop dick. Then turn her around and mushroom print her forehead with your poop dick.
I remember this girlfriend from back in high school. I found out she was banging my dad, so I gave her the Shiitake Mushroomand dumped her!
by *Dirty Dave* September 13, 2009
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