Oratory, Congregation of the, community of secular priests formed by St. Philip of Neri (q.v.), and bound by no religious vow, each one of which is independent of the others; it consists of novices, triennial fathers, decennial fathers, and a superior, their functions being to preach and hear confession.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Oratorio * Orcagna