CHURCH SONATA

   An instrumental composition in several movements or sections, dating from the 17th or early 18th century, that might be used to substitute for organ versets in a Roman Catholic mass. The traditional term sonata da chiesa appears only infrequently in contemporary sources; any ensemble sonata using imitation and other suitable sacred idioms might be so used. Although the movement pattern of slow-fast-slow-fast was once thought to be the defining feature, the sources show a wide variety of orders.