A phrase most commonly used to describe 1) a 'decent piece' of ass. It can also describe 2) anything that is good or better. The implied meaning can vary but usually understates the quality of something that is way better than decent.
1) "I'm going to buy that girl drink. She's a dece piece."
2) "Oh you got a PSP? Dece piece."
by Carweezie July 7, 2005
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