or·a·to·ri·o (ôr′ə-tôrē-ō′, ŏr′-)
n. pl. or·a·to·ri·os
A musical composition for voices and orchestra, telling a usually sacred story without costumes, scenery, or dramatic action.
[Italian, after Oratorio, the Oratory of Saint Philip Neri at Rome, where famous musical services were held in the 16th century.]
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