tiara
/tɪˈɑːrə/noun
1
- a jewelled ornamental band worn on the front of a woman's hair（饰有珠宝的女用）冕状头饰。
2
- a high diadem encircled with three crowns and worn by a pope（教皇的）三重冕。
2.1
- historical a turban worn by ancient Persian kings〈史〉（古代波斯国王的）包头巾。
词源
mid 16th cent. (denoting the Persian royal headdress)： via Latin from Greek， partly via Italian. Sense 1 dates from the early 18th cent.