A ritornello (Italian; "little return") is a recurring passage in Baroque music for orchestra or chorus. The first or final movement of a solo concerto or aria may be in "ritornello form", in which the ritornello is the opening theme, always played by tutti, which returns in whole or in part and in different keys throughout the movement, in which particulars the form differs from the rondo.

Ritornello form was favoured by Bach, Vivaldi, Telemann and Handel in chamber works, vocal pieces and, most prominently, in the solo concerto in a ‘tutti-solo-tutti-solo-tutti’ pattern in which the ritornello, the ‘tutti’ section, functions as a refrain or chorus while the solo sections may expand upon the short melodic lines of the tutti. At the end of the movement the entire ritornello returns in the home key. J.S. Bach's Brandenburg_Concertos offer excellent examples. In opera seria, the ritornello functioned as the main structural support for the da capo aria, in which it was successively repeated.

The final section of a fourteenth century madrigal had previously been called the ritornello and a similar technique had been employed by Giovanni Gabrieli in his 16th century motets. The instrumental interludes in early Baroque operas were also termed ritornelli.

Ritornello construction faded with the advent of the new sonata form but received renewed interest in the 20th century .

References

• Warrack, John and West, Ewan (1992), The Oxford Dictionary of Opera, 782 pages, ISBN 0-19-869164-5