ˌȯrəˈtōrēˌō, ˌärə-, -tȯr- noun
( -s )
Etymology: Italian, from the Oratorio di San Filippo Neri (Oratory of St. Philip Neri) in Rome, where musical religious services similar to mystery plays were held in the 16th century
1. : a musical composition having a libretto based usually on a religious or scriptural subject and consisting typically of recitatives, arias, choruses, orchestral interludes and accompaniment, and sometimes spoken dialogue or narration but having no action, scenery, or costume
2. : a performance of such a composition