A congenital deformity in which the buttocks can open up like the shells of a clam, with anus inside as a clam would be inside clamshells.
He dropped his shorts and then made everyone in the locker-room pass out from the sight of his clamshell anus.
by wiginpen February 15, 2004

The sensation that one's sphincter is actually aflame, usually occurring after eating bad tex-mex, taking a really nasty shit, or pulling the Steve-O Bottle Rocket stunt from JACKASS NUMBER TWO...
GUY1: Dude, why did I have to go to Chipotle on my lunch break? Now I've got to sit through this board meeting with my heinous anus! My Asshole must look like a cigarette burn on the Sunday morning comics!
by Mjolnir12982 April 18, 2010

by Brikalyn January 8, 2014

"Look! Did Kate just shove that huge cactus up her anus?!"
"Yeah that's a Cactus in anus all right !"
"Yeah that's a Cactus in anus all right !"
by Hycelot July 31, 2016

by AAaaalRightythen March 7, 2008

by TurtleGamer1993 June 28, 2015

1. Something given or paid in addition to what is usual or expected.
2. Something good, extra, free or unexpected.
2. Something good, extra, free or unexpected.
Oprah - "You get a car! You get a car! EVERYBODY GETS A CAR!!"
Random audience member slash receiver of new awesome Oprah car - "BONUS ANUS!"
Random audience member slash receiver of new awesome Oprah car - "BONUS ANUS!"
by dirtydawgggggg November 8, 2010
