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The act of breaching the water with ones ass like a whale breaching for a breath of air.
I gave the life guard at the public swimming pool a rumpback whale and they banned me for the summer.
by Hardly brothers July 27, 2009
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2
The ass-like crack formed by a fat lady wearing a tight bathing suit in the middle of her back.
by Hhead August 27, 2013
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