Dump Ring

When a large, long, and fairly sturdy turd strikes the inside of a toilet bowl, and is then flushed. It will often create a circular smudge or smear around the inside of the bowl. This term was coined by a woman living somewhere in the Midwest, USA after her son deposited such a turd into her toilet bowl and attempted to flush, but he left it for her to discover the next morning.

"Who left the giant 'dump ring' in my toilet!!!"