1. The act of taking consecutive shits in the same toilet without flushing. This also occurs when onsecutive hot piles are dropped in any location other than a toilet, and it is most commonly found in an outhouse at a chili cook-off.

2. Also a nickname for a short stack of chocolate chip pancakes at IHOP.
The couple was disappointed that their poostack count lowered when they moved into an apartment with two bathrooms.
by wordman55 August 27, 2012
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