Top definition
A poo that is so large or messy that it defies definition.
Bill: How was that deuce, Jim?

Jim: It was pooposterous! I think I emptied my entire colon.
by T. Stunt March 24, 2017
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2
contrary to reason or common sense, utterly absurd or ridiculous in the context of shit
steve- i know it was you who shit on face last night while i was passed out drunk
tom- calm down steve, just put down the microwave it wasnt me
steve- that pooposterous! theres poop all over your hand, i caught you shit hannded, and now your gona get the shit handed to you real good
by rawdogkilla November 10, 2013
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