Main Entry: or·a·to·rio

Pronunciation: \ˌȯr-ə-ˈtȯr-ē-ˌō, ˌär-\

Function: noun

Inflected Form(s): plural or·a·to·ri·os

Etymology: Italian, from the Oratorio di San Filippo Neri (Oratory of St. Philip Neri) in Rome

Date: 1731

: a lengthy choral work usually of a religious nature consisting chiefly of recitatives, arias, and choruses without action or scenery