Heptachord
Pronunciation : Hep"ta*chord
Part of Speech : n.
Etymology : [Gr. "epta`xordos seven-stringed; "epta` seven + xordh` chord: cf. F. heptacorde. See Seven, and Chord.]
Definition : 1. (Anc. Mus.) (a) A system of seven sounds. (b) A lyre with seven chords.
2. (Anc. Poet.)
Defn: A composition sung to the sound of seven chords or tones. Moore (Encyc. of Music).
Source : Webster's Unabridged Dictionary, 1913