'Hexachord' definitions:

Definition of 'Hexachord'

From: GCIDE

Hexachord \Hex"a*chord\, n. [Hexa- + Gr. ? string, chord: cf. F. hexacorde.] (Mus.) A series of six notes, with a semitone between the third and fourth, the other intervals being whole tones. [1913 Webster]