/ Dictionary / Index S seventh chord: Meaning and Definition of Find definitions for: sev'enth chord" Pronunciation: [key] — Music. Music. a chord formed by the superposition of three thirds. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Seventh Avenue Seventh Commandment Related Content Daily Word Quiz: industrious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language