Money-spinner goes on line in The Apprentice (7)
I believe the answer is:
learner
'the apprentice' is the definition.
('learner' can be a synonym of 'apprentice')
'money-spinner goes on line' is the wordplay.
'money-spinner' becomes 'earner' (I've seen this before).
'goes on' is a charade indicator (letters next to each other).
'line' becomes 'l' (used when specifying particular lines from a poem).
'earner' put after 'l' is 'LEARNER'.
'in' acts as a link.
(Other definitions for learner that I've seen before include "who needs plates" , "Unqualified driver" , "Pupil or apprentice" , "neophyte" , "Novice driver" .)