/ Dictionary / Index O octachord: Meaning and Definition of Find definitions for: oc•ta•chord Pronunciation: (ok'tu-kôrd"), [key] — n. any musical instrument with eight strings. a diatonic series of eight tones. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. octa- octad Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language