What type of musical composition features a solo instrument or instruments accompanied by an orchestra?

A concerto is a musical composition designed to showcase a solo instrument or a group of instruments, with the accompaniment of an orchestra. This genre typically contrasts the virtuosity and expressiveness of the soloist with the broader orchestral forces, allowing for a dynamic interplay between the two. The structure of a concerto often includes multiple movements, with the first movement typically following a sonata form that emphasizes the thematic dialogue between the soloist and the orchestra.

Sonatas, on the other hand, usually focus on solo instruments or a duo (like piano and violin), and do not typically involve orchestral accompaniment. Symphonies are large-scale orchestral works that do not feature solo instruments in the same prominent way as concertos. Overtures serve as introductory pieces for operas or other larger compositions and are not structured to highlight a singular soloist in accompaniment with an orchestra. Thus, the definition and characteristics of a concerto distinctly align with the concept of featuring a solo instrument or instruments alongside an orchestra.