When one is in the middle of an act with a preferably big audience and cannot hold in one's feces. To release the individual's feces they are forced to squat on stage and release their feces into their delicates.
Brian forgot to take his anti-diarrheal but the show must go on.

Brian: *squats on stage*
Susie: What are you doing!?
Brian: Taking a theatre dump.
Audience: *laughs*
by cookiemonsterthepimp November 6, 2019
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