chrōma, ătis (ătŏs, Vitr. 5, 5), n., = χρῶμα (a color), in music,
I a chromatic scale (a species of harmony in which the tones of the tetrachord measure two and a half tones, as a half, again a semitone, and then a tone and a half follow each other), Vitr. 5, 4, 3; cf. Dict. of Antiq. p. 645.
II —Hence, chrōmătĭcē , ēs, f., the science of this species of harmony , Vitr. 5, 5; and: chrō-mătĭcus , a, um, adj., chromatic : genus, the same, Macr. Somn. Scip. 2, 4 fin.