Diadem in Smiths Bible Dictionary
What the "diadem" of the Jews was we know not. That of other
nations of antiquity was a fillet of silk, two inches broad,
bound round the head and tied behind. Its invention is
attributed to Liber. Its color was generally white, sometimes,
however, it was of blue, like that of Darius; and it was sown
with pearls or other gems, Zec 9:16 and enriched with gold. Re
9:7 It was peculiarly the mark of Oriental sovereigns. In Es
1:11; 2:17 we have cether for the turban worn by the Persian
king, queen or other eminent persons to whom it was conceded
as a special favor. The diadem of the king differed from that
of others in having an erect triangular peak. The words in Eze
23:15 mean long and flowing turbans of gorgeous colors.
[CROWN]
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