Meaning of sodium tripolyphosphate

so'dium tri•pol•y•phos'phate

Pronunciation: (trī"pol-ē-fos'fāt), [key]
— Chem. Chem.
  1. a white powder, NaPO, used as a water softener, sequestering agent, and food additive. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.