From The Collaborative International Dictionary of English v.0.48 [gcide]:
Diadem \Di"a*dem\, v. t.
To adorn with a diadem; to crown.
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Not so, when diadem'd with rays divine. --Pope.
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To terminate the evil,
To diadem the right. --R. H. Neale.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Diadem \Di"a*dem\, n. [F. diad[`e]me, L. diadema, fr. Gr. ?, fr.
? to bind round; dia` through, across + ? to bind; cf. Skr.
d[=a] to bind.]
1. Originally, an ornamental head band or fillet, worn by
Eastern monarchs as a badge of royalty; hence (later),
also, a crown, in general. "The regal diadem." --Milton.
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2. Regal power; sovereignty; empire; -- considered as
symbolized by the crown.
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3. (Her.) An arch rising from the rim of a crown (rarely also
of a coronet), and uniting with others over its center.
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Diadem lemur. (Zool.) See Indri.
Diadem spider (Zool.), the garden spider.
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From WordNet (r) 3.0 (2006) [wn]:
diadem
n 1: an ornamental jeweled headdress signifying sovereignty
[syn: crown, diadem]