The mitre ("headband" or "turban"), also spelled miter (see spelling differences), is a type of headgear now known as the traditional, ceremonial head-dress of bishops and certain abbots in traditional Christianity; continuing the priestly practice of Temple Judaism.

The letters on the Pope's mitre are these: "Vicarius Filii Dei," which is Latin for "Vicar of the Son of God". Contrary to some claims, no tiara has ever been inscribed with the phrase Vicarius Filii Dei.

Cardinals are now normally supposed to be bishops (since the time of Pope John XXIII), but even cardinals who are not bishops and who have been given special permission by the pope to decline consecration as bishops may wear the mitre.

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