Unison [prime] (Fr. unisson; Ger. Prime; It. prima)
- Julian Rushton
(1) Two or more notes sounding the identical pitch, usually though not necessarily at the same time. In a number system with semitone = 1, tone = 2, the unison ‘interval’ is equivalent to zero. It would be theoretically possible to call the interval C–C♯ an ‘augmented unison’ but in practice it is normally referred to simply as a chromatic semitone. Similarly, ...