/ Dictionary / Index E equivalence relation: Meaning and Definition of Find definitions for: equiv'alence rela"tion Pronunciation: [key] — Math. Math. a relation that is reflexive, symmetrical, and transitive, as equality. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. equivalence principle equivalency Related Content Daily Word Quiz: secular Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language