A crap so bad it is said to stain the toilet bowl. This can be due to the size of the crap, or, alternatively, because of the painful feeling incurred before or during said crap, probably caused by the food ingested to create the aforementioned crap.
Don't go in there yet. I just dropped a bowlstainer.
by Mike P. Grant, Esq. May 10, 2007
brown streaks left in the bowl after taking a crap
I peered into the stall and saw one of my coworkers bowl staining.
by brian meade February 20, 2004