It's usually a tiara or something sparkly, like a crown
I am wearing a diadem.
The diadem was one of Tom Riddle's Horcruxes. A diadem is like a sort of crown.
Diadem of gold or precious stones.The queen wore diadem of jewels and gold
Operation Diadem happened in 1944.
She adorned her head with a sparkling diadem for the royal ball.
A zodiac diadem is an ASTROLOGICAL CROWN. or something very similar to that.
Madonna with the Blue Diadem was created in 1511.
Mograbin diadem snake was created in 1923.
The diadem was hidden in the Room of Requirement
George IV State Diadem was created in 1820.
The ancient diadem was the highly adorned and richly gemmed head-dress, worn by kings. In the east the diadem was a symbol of absolute power.The diadem was usually a headband about two inches wide, tied in the back and made of silk, and inlaid with gold and the most precious gems. The crown was a symbol of glory, and the diadem was a symbol of beauty.
A crown or tiara.