diadem

n. crown; decorative wreath; item that decorate like a crown

Diadem has a number of different meanings, including the following:A diadem is a type of crown.Diadem is the brightest star in the constellation Coma Berenices.A diadem may be one of several tropical butterflies in the genus Hypolimnas.Diadem is a series of books by John PeelThe Diadem Saga is a science fiction series by author Jo ClaytonA user interface for the DIPPR 801 databaseHMS Diadem was the lead ship of the Diadem-class of protected cruiser in the Royal Navy launched in 1896.HMS Diadem was a cruiser of the Royal Navy in World War II.DIAdem is a technical software for managing, analyzing, and reporting technical data from National InstrumentsA Diadem is also a shape of stone. This was shown on Nicolas Poussin's finger in his Self Portrait of 1650. It represents Constintina (strength of character)."Diadems" is a song by american thrash metal band, megadeth. It features on the album Hidden Treasures.Operation Diadem was a military operation in the Second World War's Italian Campaign.This is not to be confused with Diadema, which can also take several meanings.
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Noun
1. an ornamental jewelled headdress signifying sovereignty
(synonym) crown
(hypernym) jewelled headdress
(hyponym) coronet

n. crown, diadem, wreath, circular ornament, coronet, crown-like ornament worn on the head

(v. t.)
To adorn with a diadem; to crown.
  

(n.)
Regal power; sovereignty; empire; -- considered as symbolized by the crown.
  

(n.)
Originally, an ornamental head band or fillet, worn by Eastern monarchs as a badge of royalty; hence (later), also, a crown, in general.
  

(n.)
An arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its center.