/ Dictionary / Index O optimist: Meaning and Definition of Find definitions for: op•ti•mist Pronunciation: (op'tu-mist), [key] — n. an optimistic person. a person who holds the belief or the doctrine of optimism. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: optimist (Thesaurus) optimism optimistic Related Content Daily Word Quiz: frugal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language