Why is the ninth month called September?
bishop's tall hat, late 14c., from Old French mitre, from Latin mitra "headband, turban," from Greek mitra "headband, turban," earlier a belt or cloth worn under armor about the waist, from PIE root *mei- "to tie" (cf. Sanskrit Mitrah, Old Persian Mithra-, god names; Russian mir "world, peace," Greek mitos "a warp thread"). In Latin, "a kind of headdress common among Asiatics, the wearing of which by men was regarded in Rome as a mark of effeminacy" [OED]. But the word was used in Vulgate to translate Hebrew micnepheth "headdress of a priest."
(Heb. mitsnepheth), something rolled round the head; the turban or head-dress of the high priest (Ex. 28:4, 37, 39; 29:6, etc.). In the Authorized Version of Ezek. 21:26, this Hebrew word is rendered "diadem," but in the Revised Version, "mitre." It was a twisted band of fine linen, 8 yards in length, coiled into the form of a cap, and worn on official occasions (Lev. 8:9; 16:4; Zech. 3:5). On the front of it was a golden plate with the inscription, "Holiness to the Lord." The mitsnepheth differed from the mitre or head-dress (migba'ah) of the common priest. (See BONNET.)
liturgical headdress worn by Roman Catholic bishops and abbots and some Anglican and Lutheran bishops. It has two shield-shaped stiffened halves that face the front and back. Two fringed streamers, known as lappets, hang from the back. It developed from the papal tiara and came into use in the 11th century.