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1 definition by Mike Feig

A large muscular butt. Found mostly in mountainous regions as a result of walking in the mountains, but could also be achieved by working out the glutios maximus. Pertains to the curve coming down the back to the ass that sticks out far enough to rest a drink on it. Does not pertain to hips.
Look at the mountain butt on that chick!!!
by Mike Feig January 07, 2007