Ag•nus De•i(äg´noos dā´ē´, ag´nəs-, än´yōs´-; -dē´ī´)

 1 a representation of Christ as a lamb, often holding a cross or flag
 2 R.C.Ch.
 a) a little wax disk with a lamb pictured on it, blessed by the pope
 b) a prayer in the Latin Mass, beginning Agnus Dei
 c) music for this