allegro [I]—fast, lively tempo. From the Italian word for cheerful or gay.
andantino—faster than andante, slower than allegretto. Sometimes andantino is interpreted as the opposite: slower than andante
chamber music, Kammermusik [G], musique de chambre [F], musica da camera [I], musica cameralis [L]—"Classical Music" for a small ensemble, generally 8 or fewer players with a canonical emphasis on 3-6 players. explore
opus [L], opera[pl], Op., Opp, WoO, Op. posth—work, as in a work of art. For unique identification, publishers/composers often assign an "opus number", abbreviated as "Op." (e.g. Op. 1). A range of works by opus number, uses the plural "opp." (e.g. "Opp. 1-3"). A single opus number may refer to a collection of works (e.g. a set of quartets) giving rise to designations like "Op. 1, No. 4". For misc. works without opus numbers, "WoO" is often used (e.g."Without Opus"). Posthumously assigned numbers may use "Op. posth". Opus numbers may not precisely reflect chronology (publication vs. composition), can be erroneous, sparse or duplicative. Thus, the works of some historically important composers may use separate catalog numbers (e.g. Bach, Haydn, Schubert). See wiki
Polonaise [F], Polonese [I], Polacca [I], Polaca, alla polacca, Polones—a dance of Polish origin in a moderate triple meter (3/4) typically with a characteristic rhythm (subdivisions of the beat with a flourish in the 2nd half of the 1st beat) and an energetic momentum.
quartet, quatuor [F], quartett [G], quartetto [I], cuarteto [S]—ensemble or work for four players the most important examples being the string quartet and the piano quartet
tema con variazioni, con variazioni, Tema e variazioni, theme and variations, Thema mit Variationen [G], Thème varié [F]—a common movement form featuring an initial theme followed by a series of variations on that theme, each of which adjusts any number of parameters to achieve variety, e.g. tempo, rhythm, key, instrumentation, etc.A challenge to the composers ingenuity and a delight for the listener
variation, variazione, variatio, variato, variata—a modified re-iteration of a previous theme, reprise, couplet, etc. The music is varied, embellished or creatively transformed for variety while maintaining a unity relationship with the original. See "Theme and Variations."