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A membership organization in which to belong you must have taken a dump thought to be a clean swiper (little toilet paper used) and found upon said swipe a muddy mess with doody (feces) all over the paper even under your fingernail. Once you experience this you are officially, like or not, a member of the Muddy Doody Society (MDS)
Man #1: Hey man sorry I took so long, thought I was going to have an easy time in there but fell pray to the Muddy Doody Society.

Man #2: Shit man your first time becoming a member of the MDS?

Man#3: Hell no my wife checks my fingernails before we go to bed at night and she makes sure I have my membership card in my wallet.
by Looneylarry April 04, 2012