Di"a*dem (?), n. [F. diademe, L. diadema, fr. Gr. , fr. to bind round; through, across + to bind; cf. Skr. da 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.
2.
Regal power; sovereignty; empire; -- considered as symbolized by the crown.
3. Her.
An arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its center.
Diadem lemur. Zool. See Indri. -- Diadem spider Zool., the garden spider.
© Webster 1913.
Di"a*dem, v. t.
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.
© Webster 1913.