D defs.my
Entry 4 senses · 2 variants Webster, 1913

Diadem

/dī'ədem/ · Di·a·dem · IPA /ˈdaɪ.əˌdɛm/
01 n. Originally, an ornamental head band or fillet, worn by Eastern monarchs as a badge of royalty; hence (later), also, a crown, in general.
  1. 1.
    Originally, an ornamental head band or fillet, worn by Eastern monarchs as a badge of royalty; hence (later), also, a crown, in general.
  2. 2.
    Regal power; sovereignty; empire; -- considered as symbolized by the crown.
  3. 3.
    An arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its center.(Her.)
Phrases & compounds
Diadem lemur — See Indri.
Diadem spider — the garden spider.
02 v. t. To adorn with a diadem; to crown.
  1. 1.
    To adorn with a diadem; to crown.
    “Not so, when diadem'd with rays divine.” Pope.
    “To terminate the evil, To diadem the right.” — R. H. Neale.