The sphere of royalty (3)

I believe the answer is:

orb

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'the sphere' is the definition.
(orb is a kind of sphere)

I cannot understand how the remainder of the clue works.

(Other definitions for orb that I've seen before include "Item of royal regalia" , "Sphere - eye" , "Part of royal regalia" , "Celestial body; sphere" , "component of royal regalia" .)

I've seen this clue in the Evening Standard.

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