/ Dictionary / Index S Sunday supplement: Meaning and Definition of Find definitions for: Sun'day sup'plement Pronunciation: [key] a special section incorporated in the Sunday editions of many newspapers, often containing features on books, celebrities, home entertainment, gardening, and the like. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Sunday school sun deck Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language