Mus. [ad. med.L. tritonus, ad. Gr. τρίτονος, f. τρι-, TRI- + τόνος TONE.] An interval consisting of three whole tones; an augmented fourth. (Also formerly in Latin form.)
1609. Douland, Ornith. Microl., 20. A Tritone doth exceed the Consonance of a Diatessaron.
1730. Treat. Harmony, 7. The Leaps of the False Relations, viz. of a Tritonus, and of a Semidiapente are … forbidden.
1775. Steele, in Phil. Trans., LXV. 76. Tritones, or sharp fourths, above the upper minims.
1789. Burney, Hist. Mus. (ed. 2), III. vii. 344. The Tritonus … consisting of three tones, without the intervention of a semitone, is extremely difficult to sing.
1854. Cherubini’s Counterpoint, 11. It now remains to be demonstrated how and why the Tritone is a false relation in harmony.
