When a dude proudly displays the size of his unusually large shit to another man or group of men, to gain pride and respect among his fellow bros.
A typical poopularity contest:

Andrew: "Hey John, check out the size of this enormous SHIT i took!!! You wont believe that this thing actually came out of my ass!!! I... I think its moving..."

John: "Ill be right there, bro......... Whoa, i bet that weighs more than a baby, good one dude, keep up the good work. Let me take a picture so I can post it to my twitter..."
by mothercocker May 4, 2011
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