​SHARP (Diesis, from Lat. Divisio; Fr. Dièse). The term which expresses the raising of a note by a less quantity than a whole tone. F sharp is half a tone higher than F natural: a singer 'sang sharp'—that is, sang slightly higher than the accompaniment; 'the pitch was sharpened'—that is, was slightly raised.

The sign for a sharp in practical music is ♯; for a double sharp, two half tones, ×. In French the same signs are used, but the raised note is entitled dièse—Fa dièse, Ré dièse, etc.; in German Fis, Dis, etc., just as E♭, G♭ are designated Es, Ges, and so on.

The sign is said to have originated^[1] in the fact that in the 15th and 16th centuries the tone was divided into five intervals, which were designated by ×, ♯, , ^{(Music characters)}, according to the number of parts represented by each. These gradually fell into disuse, and the second alone remained. In the printed music of the 17th century however the sign is usually .

In Germany the sign was used to express the major mode, C♯ meaning C major, A♯, A major, and so forth. Thus Beethoven has inscribed the overture to Leonora known as 'No. 1' (which is in the key of C) with the words 'Ouvertura in C♯, Characteristische Ouverture.' The Eroica Symphony, in E♭, was even announced in the programme of Clement's Concert, April 7, 1805, as 'Eine neue grosse Sinfonie in Dis' (i.e. D♯). Instances of the practice are frequent in the Index to the 'Allgemeine musikalische Zeitung.'