Tiara (?), n. [L., from Gr. &unr_;, &unr_;; of Persian origin.] 1. A form of headdress worn by the ancient Persians. According to Xenophon, the royal tiara was encircled with a diadem, and was high and erect, while those of the people were flexible, or had rims turned over.
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2. The pope's triple crown. It was at first a round, high cap, but was afterward encompassed with a crown, subsequently with a second, and finally with a third. Fig.: The papal dignity.
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