diadem

A diadem is a circular band or fillet worn around the head, often jeweled, that serves as a symbol of sovereignty or rank. It refers to a type of crown, typically lighter and more restricted in coverage than a full crown, and is usually a circlet or open band rather than a tall, encircling headdress.

The term comes from the Latin diadema, from the Greek diádēma, meaning a band worn around the head. Diadems have appeared in many cultures. In the ancient Near East, Mesopotamian, Egyptian, Persian, and Hellenistic kings wore jeweled headbands as insignia of authority. In ancient Greece and Rome, diadems were associated with royal power and divine favor. Byzantine empresses and other medieval and early modern monarchs continued to use diadems in ceremonial contexts, particularly for queens and empresses.

Designs vary from simple gold bands set with a few gems to elaborate tiara-like circlets with multiple arches or terminal points and motifs such as laurel leaves, stars, or floral patterns. They are often worn at formal occasions, coronations, weddings, or state events, and may be built to hinge or be adjustable to fit the wearer.

In modern usage, diadems are primarily ceremonial jewelry and are featured in royal regalia and museum collections. They symbolize sovereignty, legitimacy, and the continuity of authority, and appear in heraldry and portraiture as emblems of regal status.