The hole located at the end of your rectum that secrets brown substances. Also known as your anus and can be used for anal sex.
"Let me see that Brownhole!"
by Geoff Schwab May 20, 2008
1/2 way between a black hole & white hole...
You are on the edge of a galaxy event horizon looking toward center then you see brown hole.
by sinbad_duke_of_east_los March 20, 2007