Item of regalia (3)
I believe the answer is:
orb
'item of regalia' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for orb that I've seen before include "Royal sphere (paired with 13 across)" , "Spherical symbol of monarch's power" , "A sphere or globe" , "Heavenly body" , "Item of insignia" .)