1 definition by michaelfishywishywish.

Shortened and somewhat corrupted pronunciation of the derogatory word 'dumbass'. Used to describe some kind of fool, or someone who's made a particularly foolish mistake, or some kind of epic fail.

Quite notably created by the infamous Dylan Basnett, along with other such words such as 'PAIN' and 'CREM'.
Dylan: I thought the current prime minister was Tony Blair?
Jack: MASS Dylan! Old Blair got the boot eons ago.
by michaelfishywishywish. July 21, 2010
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