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1 definition by Coco Loco Croco

 
1.
In the Song "F*ck the pain away" by Peaches one of the lyrics is IUD SIS then later she mentions to stay in school
the acronym siply means "Stay in School, Injustice Under Dog"
"IUD SIS, Stay in school 'Cause it's the best."
simply Backwards SIS IUD

IUD SIS or SIS IUD
by Coco Loco Croco October 14, 2008