andante—moderately slow tempo (e.g. walking). Faster than adagio but slower than allegretto
chamber music, Kammermusik [G], Musique de chambre [F], Musica da camera [I]—"Classical Music" for a small ensemble, generally 8 or fewer players with a canonical emphasis on 3-6 players
duo, duet, dueto [S], duetto [I], duett [G]—a work for two instruments; the ensemble itself
moderato [I], moderamente, modéré [F], modérément [F]—moderately, at a moderate tempo, applying a touch of restraint to its related word(s), e.g. allegro moderato
sonata, sonate, suonato—a complicated term. Originally, "sounded" rather than "sung" (sonar vs. cantar), e.g. instrumental music. According to historical period, sonata began to imply a formal plan of movements as well as the structure within a single movement, e.g. sonata form. In general usage as a work title, it designates a multi-movement piece for solo or duo instruments with one of the instruments enjoying a feature role.
violin sonata—a multi-movement work for violin and keyboard (or continuo) though there are sonatas for solo violin as well as sonatas in a single movement. While the violin would seem to be the featured instrument, many sonatas starting with the classical period find the piano to be an equal partner in the sense of a chamber work for two players.
with thinking heart and feeling mind, I'll embody your muse, thy soul divine