patera

Pat"e*ra, n.; pl. Pateræ(. Etym: [ L., fr. patere to lie open.] 1. A saucerlike vessel of earthenware or metal, used by the Greeks and Romans in libations and sacrificies. 2. (Arch.) Defn: A circular ornament, resembling a dish, often worked in relief on friezes, and the like.

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