/ Dictionary / Index F forsterite: Meaning and Definition of Find definitions for: for•ster•ite Pronunciation: (fôr'stu-rīt"), [key] — n. Mineral. the magnesium end member, MgSiO, of the olivine group. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Forster Forstner bit Related Content Daily Word Quiz: perspicacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language