Tonus, toni, mas. ge. Tune or accent. Also the space betweene the earth and the Moone.
Lewis and Short: Latin dictionary
tŏnus, i, m., = to/nos.I.The stretching, straining of a rope: mollior, vehementior, Vitr. 10, 10, 6. — II.Trop.A.Lit., the sound, tone, of an instrument, Vitr. 5, 4; Macr. Somn. Scip. 2, 1 med.; Mart. Cap. 9, 959.—Of the tone of a syllable, accent, Nigid. ap. Gell. 13, 25, 1 sq.—B.Transf.1. Like our tone, in painting, of the natural color of an object, Plin. 35, 5, 11, 29.—2. For tonitrus, thunder, Sen. Q. N. 2, 56, 1.