Where you sit on someone's chin and shart.
I'm going to shast mast you in your sleep.
by Hazzardouspat May 13, 2015
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When somebody is either disappointed or amazed at something. Another way of saying shit.
The huskers lost in OT today.. Shast piece.

or

I just ate 10 hot dogs for lunch today.. Shast piece
by The Jankster 88 June 25, 2010
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