Concerto is now used to designate a work in which one solo instrument, sometimes more, is contrasted with a larger instrumental group (conventionally a full symphony orchestra); the term was first used in the 17th cent. to describe music written for voices and instruments. But it was the concerto grosso, as perfected by Corelli at the turn of the 18th cent., that began the evolution of the form, which reached its high point in the vehicles for virtuoso display of the romantic era — Andrew Clements