Symphony (Gr. σύυ with, and φωνή voice), a term originally signifying merely a concordance of tones, but applied successively to certain vocal compositions, to compositions partly vocal and partly instrumental, to short introductory or intermediate instrumental passages in compositions which are predominantly vocal, and finally to elaborate and extended compositions for instruments only and in the sonata form. In this sense the word is now generally used. The germ of the modern symphony may be found in the suites prefixed by Scarlatti to his operas, which he designated as the symphony, consisting of three movements: 1, allegro; 2, andante; 3, allegro. But it was not till the time of Haydn, called the father of the symphony, that this kind of composition took its present form. He added a fourth movement, the minuetto, and elaborated the whole structure of the symphony. He composed 118 works of this kind. The form that Haydn fixed upon was adopted by Mozart and Beethoven, the latterespeciallygiving a breadth, dignity, and grandeur to his symphonies that have made them the masterpieces of this form of musical art. In the final movement of his ninth or choral symphony he introduced vocal music, an example which has not been followed by later composers.

Mendelssohn, Gade, Rei-necke, Liszt, and Raff are among the more modern composers of works of this class.