/ Dictionary / Index S symmetric difference: Meaning and Definition of Find definitions for: symmet'ric dif'ference Pronunciation: [key] — Math. Math. the union of the relative complements of two sets. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. symmetrical symmetric function Related Content Daily Word Quiz: neologism Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language