HARMONY - (1) The procedure by which chords of music are constructed and (2) the system by which one chord follows another chord in time. To make harmony distinct from "interval", harmony is the simultaneous occurance of THREE or more tones. (Scd92)

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harmony used by accompaniment
harmony has element tonality
harmony is vertical aspect of music
harmony has role in key
harmony sometimes involved with accompaniment
harmony supports melody
harmony has basis harmonic series
harmony has basis intervals
harmony used to create song
harmony contains chords
harmony contains intervals
harmony has timbral resource instruments
harmony has quality consonance
harmony has quality dissonance
harmony has/have "treatment" style
harmony may be element of composition
harmony element 3 of Elements of Music