/ Dictionary / Index I isopyre: Meaning and Definition of Find definitions for: i•so•pyre Pronunciation: (ī'su-pīr"), [key] — n. Mineral. an impure variety of opal, containing alumina, lime, and iron sesquioxide. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. isopycnic iso-reel Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language