/ Dictionary / Index D definition: Meaning and Definition of Find definitions for: def•i•ni•tion Pronunciation: (def"u-nish'un), [key] — n. the act of defining or making definite, distinct, or clear. the formal statement of the meaning or significance of a word, phrase, etc. the condition of being definite, distinct, or clearly outlined. sharpness of the image formed by an optical system. the accuracy of sound or picture reproduction. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: definition (Thesaurus) definite relative pronoun definitive Related Content Daily Word Quiz: diaphanous Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language