The Royal Ball (3)
I believe the answer is:
orb
'the royal ball' is the definition.
(I've seen this in another clue)
'royal ball' is the wordplay.
I cannot really see how this works, but
'royal' could be 'r' (abbreviation) and 'r' is found in the answer.
'ball' could be 'o' (O looks like a ball) and 'o' is present in the answer.
A single letter 'b' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for orb that I've seen before include "Celestial body; sphere" , "Spherical symbol of monarch's power" , "ball with cross" , "Poetically eye" , "The World" .)