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1.
Otherwise termed freezing one's ass off, is a condition resulting from prolonged exposure of one's ass (booty/butt/buns/etc) to cold weather.
Often caused due to poor clothing choice that is not adequate to cover the buns. Condition results in numbness of the seating areas (apart from terrible bodily aches results from the frozen extremities).
ass + hypothermia = assmothermia

(Term coined by DC resident Marcia Pincus after suffering a bout of assmothermia during the 4th day of the 2010 record snow storm)
John has a severe case of assmothermia after walking a mile in the biting cold.
by Transportgooru February 10, 2010