Avodah (Hebrew, Service) is the description of the complicated sacrificial ritual practiced in the Jerusalem Temple on the Day of Atonement, and now is recited as the central part of the Musaf service on that day. Its basis is Leviticus 16, and is described in the Misnah (Yoma 1-7). The reading is enriched by by various piyyutim, Jewish poems, composed during the Middle Ages. A.G.H.
Bowker, John, The Oxford Dictionary of World Religions, New York, Oxford University Press, 1997, p. 115