Balls or ballocks? (4)

I believe the answer is:

orbs

I'm a little stuck... Click here to teach me more about this clue!

'balls' is the definition.
('orb' can be a synonym of 'ball')

'or ballocks?' is the wordplay.
'ballocks?' becomes 'bs' (I can't justify this - if you can you should believe this answer much more).
'or'+'bs'='ORBS'

Can you help me to learn more?

(Other definitions for orbs that I've seen before include "Ball shapes" , "Poetic eyes, bros" , "Eyeballs" , "circles" , "Spherical shapes" .)

I've seen this clue in the Sydney Morning Herald.

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