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1 definition by max636

 
1.
n. When the fabric on the butt of jeans stretches and no longer fits tightly. Called "diaper butt" because of the baggy appearance, similar to a diaper full of poop.
Term can be applied to swim suits.
"Aw man, I haven't washed these pants in about 3 days. They're all stretched out and look like diaper butt."
by max636 May 18, 2008