A breed of canine that has a tail strategically placed so that it permanently displays its arsehole. Espescially prominent on light coloured dogs.
Look at that bloke over there walking his butt mutt. Why do people think that sort of thing is attractive, I mean bloody hell, the dog keeps winking at me with its backside and putting me off my subway sandwich!
by Charverharver January 10, 2010
Compared to hot poopie, mutt butt slides right out, no pain, no worries. also caused by long periods of eating only greasy saturated foods. ie. KFC
by Christianking January 29, 2008
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