Any turd, though usually a variety of diarrhea, that contains visible husks of corn and/or beans.

Originating from the fecal movement following the consumption of 'Southwest-Style' Salsa or 'Southwest Tacos' that contain corn and/or black beans.
I barely made it! I had a turtle-head poking through when I got to work, and I thought it was going to be a thunderturd. After the spasmatic release, wouldn't you know - its Southwest Fallout.
by CodedElectron November 11, 2004
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