Noun
A poo that is unplanned and takes the person in question by surprise. Not to be confused with shit your pants; an Imprompoo is experienced whilst visiting the toilet for its conventional purpose.

ORIGIN
21st century
From 'Impromptu' (adjective & adverb) - done without being planned, organized, or rehearsed.
I just had a great imprompoo - totally unexpected!
by Failing Academic May 3, 2011
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When you go to the bathroom to pee but end up taking a poo.
Sorry I was a bit long in the bathroom, I had an imprompoo
by A Leethal May 14, 2021
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