/ Dictionary / Index I illusion: Meaning and Definition of Find definitions for: il•lu•sion Pronunciation: (i-l'zhun), [key] — n. something that deceives by producing a false or misleading impression of reality. the state or condition of being deceived; misapprehension. an instance of being deceived. a perception, as of visual stimulithat represents what is perceived in a way different from the way it is in reality. a very thin, delicate tulle of silk or nylon having a cobwebbed appearance, for trimmings, veilings, and the like. the act of deceiving; deception; delusion. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: illusion (Thesaurus) ill-use illusionary Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language