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
intermezzo, intermedio [S], intermède [F], interlude, Entr'acte—music that is "inserted" (or "interpolated) between two musical entities of greater importance (e.g. movements, acts, verses, etc.). Often suggests music of a lighter character, entertaining contrast or even improvisation.
Pierrot ensemble—ensemble comprising flute, clarinet, violin, cello and piano, often percussion and sometimes with voice named after Schoenberg's pioneering work of 1912, Pierrot Lunaire. For a list of works for Pierrot ensemble on earsense, Explore the Pierrot ensemble | wiki.
sextet, sextour [F], sestetto [I]—six. Ensemble (or work) for six players.
solo—a piece or section of a piece featuring a single instrumental part. Often, this implies one instrument alone but may indicate a soloist with accompaniment (e.g. continuo) especially in a section within a larger work for ensemble