/ Dictionary / Index I isosterism: Meaning and Definition of Find definitions for: i•sos•ter•ism Pronunciation: (ī-sos'tu-riz"um), [key] — n. the quality or state of being isosteric. the theory that isosteric compounds have identical or similar pharmacological action. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. isosteric isostructural Related Content Daily Word Quiz: penchant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language