Meaning of isophthalic acid

i'so•phthal'ic ac'id

Pronunciation: (ī'su-thal'ik, ī"su-), [key]
— Chem. Chem.
  1. a colorless, crystalline, slightly water-soluble solid, CHO, the meta isomer of phthalic acid: used chiefly in the manufacture of resins and plasticizers.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.