Word Study
hexachord
CIDE DICTIONARY
hexachord, n. [Hexa- + Gr. string, chord: cf. F. hexacorde.].
A series of six notes, with a semitone between the third and fourth, the other intervals being whole tones. [1913 Webster]
OXFORD DICTIONARY
hexachord, n. a diatonic series of six notes with a semitone between the third and fourth, used at three different pitches in medieval music.
Etymology
HEXA- + CHORD(1)
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