1) An ethnic friend, generally female, who stands behind you and sasses your detractors whenever they are encoutnered.

2) Something generally heard over the loudspeakers at chatham high school. Nobody really knows what it means, but your life is never the same once you've heard it.
The sasi backup will begin in 5 minutes.

Oh yeah, that girl was getting all up in my face, but my sasi backup, Laura the Fexican, out sassed her hoe ass.
by Colin March 27, 2005
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