Princeton's WordNet

1. symphony, symphonic music(noun)

   a long and complex sonata for symphony orchestra

2. symphony orchestra, symphony, philharmonic(noun)

   a large orchestra; can perform symphonies

   "we heard the Vienna symphony"

Kernerman English Learner's Dictionary

1. symphony(noun)ˈsɪm fə ni

   a piece of music for orchestra with several parts

   Beethoven's symphonies

2. symphonyˈsɪm fə ni

   used in the names of orchestras

   the Chicago Symphony

Wiktionary

1. symphony(Noun)

   an extended piece of music of sophisticated structure, usually for orchestra

2. symphony(Noun)

   harmony in music or colour, or a harmonious combination of elements

Origin: From συμφωνία.

Webster Dictionary

1. Symphony(noun)

   a consonance or harmony of sounds, agreeable to the ear, whether the sounds are vocal or instrumental, or both

2. Symphony(noun)

   a stringed instrument formerly in use, somewhat resembling the virginal

3. Symphony(noun)

   an elaborate instrumental composition for a full orchestra, consisting usually, like the sonata, of three or four contrasted yet inwardly related movements, as the allegro, the adagio, the minuet and trio, or scherzo, and the finale in quick time. The term has recently been applied to large orchestral works in freer form, with arguments or programmes to explain their meaning, such as the "symphonic poems" of Liszt. The term was formerly applied to any composition for an orchestra, as overtures, etc., and still earlier, to certain compositions partly vocal, partly instrumental

4. Symphony(noun)

   an instrumental passage at the beginning or end, or in the course of, a vocal composition; a prelude, interlude, or postude; a ritornello

The Nuttall Encyclopedia

1. Symphony

   an elaborate orchestral composition consisting usually of four contrasted and related movements; began to take distinctive shape in the 17th century, and was for long merely a form of overture to operas, &c., but as its possibilities were perceived was elevated into an independent concert-piece, and as such exercised the genius of Mozart and Haydn, reaching its perfection of form in the symphonies of Beethoven.

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