FIFTH

, in Music, one of the harmonical intervals or concords; called by the ancients Diapente.

The Fifth is the 3d in order of the concords, and the ratio of the chords that produce it, is that of 3 to 2. It is called Fifth, because it contains five terms, or sounds, between its extremes, and four degrees; so that in the natural scale of music it comes in the 5th place, or order, from the fundamental.—The imperfect, or defective Fifth, by the ancients called Semidiapente, is less than the Fifth by a mean semitone.