Sonata Form

form of a single movement, consisting of 3 main sections: the exposition, where themes are presented; the devleopment, where themese are treated in new ways; and the recapitulation, where themes return.  A concluding section, the coda, often follows the recapitulation

Bridge

(transition) In the exposition of the sonata form, a section which leads from the first theme in the tonic, or home, key to the second theme, which is in a new key.

Recapitulation

Third section of a sonata-form movement, in which the first theme, bridge, second theme, and concluding section are presented more or less as they were in the exposition, with one crucial difference: all the principal material is now in the tonic key.

Fermata

a sign meaning pause placed over the chord

fortepiano

18th or early 19th century piano, which differs from the modern piano in sound & construction

minuet and trio

(minuet) Compositional form - derived from a dance - in three parts: minuet (A), trio (B), minuet (A). Often used as the third movement of classical symphonies, string quartets, and other works, it is in triple meter (34 time) and usually in a moderate tempo.

coda

In a sonata-form movement, a concluding section following the recapitulation and rounding off the movement by repeating themes or developing them
further.

chamber music

Music using a small group of musicians, with one player to a part.

theme and variations

Form in which a basic musical idea (the theme) is repeated over and over and is changed each time in melody, rhythm, harmony, dynamics, or tone color. Used either as an independent piece or as one movement of a larger work.

scherzo

Compositional form in three parts (A B A), sometimes used as the third movement in classical and romantic symphonies, string quartets, and other works. A scherzo is usually in triple meter, with a faster tempo than a minuet.

Serenade

Instrumental composition, light in mood, usually meant for evening entertainment.

string quartet

Composition for two violins, a viola, and a cello; usually consisting of four movements.

Countermelody

Melodic idea that accompanies a main theme.

Development

Second section of a sonata-form movement, in which themes from the exposition are developed and the music moves through several different keys.

Rondo

Compositional form featuring a main theme (A) which returns several times in alternation with other themes, such as A B A C A and A B A C A B A. Rondo is often the form of the last movement in classical symphonies, string quartets, and sonatas.

Sonata-Rondo

Compositional form that combines the repeating theme of rondo form with a development section similar to that in sonata form, outlined A B A—development—A B A.

Exposition

First section of a sonata-form movement, which sets up a strong conflict between the tonic key and the new key; and between the first theme (or group of themes) and the second theme (or group of themes).

Motive

Fragment of a theme, or short musical idea which is developed within a composition.

Symphony

Orchestral composition, usually in four movements, typically lasting between 20 and 45 minutes, exploiting the expanded range of tone color and dynamics of the orchestra.