/ Dictionary / Index C coesite: Meaning and Definition of Find definitions for: coes•ite Pronunciation: (kō'sīt), [key] — n. Mineral. a rare form of silicon dioxide, a denser polymorph of quartz, originally synthesized from quartz at high temperatures and pressures: later discovered in nature. Cf. stishovite. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. coercivity coessential Related Content Daily Word Quiz: eureka Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language