A brown onion ring is the end result and combination of heat, time, and not wiping one's anus good enough. A sticky, cake-like residue builds up around the anus, which causes a stinky, sandy sensation on the rim of the anus.
I just bought new underwear, and now I can feel a brown onion ring seeping out onto them. Damn, it's hot outside!
by Dude Duderson May 27, 2012