What is disjoining two fourths; as, the diazeutic tone, which, like that from F to G in modern music, lay between two fourths, and, being joined to either, made a fifth. [Obs.] called?

diazeutic — Disjoining two fourths; as, the diazeutic tone, which, like that from F to G in modern music, lay between two fourths, and, being joined to either, made a fifth. [Obs.]. (Webster's 1913.)

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