/ Dictionary / Index I illus.: Meaning and Definition of Find definitions for: illus. Pronunciation: [key] illustrated. illustration. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. illuminometer ill-use Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language