Agnus Dei

"Lamb of God" (Latin phrase used in reference to Jesus Christ), liturgical prayer to Jesus or the music that accompanies this prayer (Roman Catholicism)

Agnus Dei is a Latin term meaning Lamb of God, and was originally used to refer to Jesus Christ in his role of the perfect sacrificial offering that atones for the sins of humanity in Christian theology, harkening back to ancient Jewish Temple sacrifices. See Lamb of God for an explanation of this. Agnus Dei is used to refer to several things related to it.
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Noun
1. figure of a lamb; emblematic of Christ
(synonym) Paschal Lamb
(hypernym) emblem, allegory
2. a liturgical prayer beginning with these Latin words
(hypernym) prayer

agnus, part of the Latin phrase "agnus dei"

A triple prayer in the sacrifice of the Mass, beginning with the words "Agnus Dei."

  

A figure of a lamb bearing a cross or flag.

  

A cake of wax stamped with such a figure. It is made from the remains of the paschal candles and blessed by the Pope.