/ Dictionary / Index M microfossil: Meaning and Definition of Find definitions for: mi•cro•fos•sil Pronunciation: (mī"krō-fos'il), [key] — n. a fossil so small that it can be studied and identified only with a microscope. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: microfossil (Thesaurus) microform microgamete Related Content Daily Word Quiz: jaundice Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language