Diadem the tiara of a king (Ezekiel 21:26; Isaiah 28:5; Isaiah 1:62); the turban (Job 29:14). In the New Testament a careful distinction is drawn between the diadem as a badge of royalty (Revelation 12:3; Revelation 1:13; Revelation 1:19) and the crown as a mark of distinction in private life. It is not known what the ancient Jewish "diadem" was. It was the mark of Oriental sovereigns. (See CROWN)