[2593] sēmitonium, iī, n. (semi u. tonus) = ἡμιτόνιον, der halbe Ton, Hyg. astr. 4, 14. Macr. somn. Scip. 2, 1, 25. Boëth. inst. mus. 1, 16 sqq.
Meyers-1905: Semitonīum
Pierer-1857: Semitonĭum