No opening for beginner as breadwinner (6)
I believe the answer is:
earner
'breadwinner' is the definition.
(a breadwinner earns money)
'no opening for beginner' is the wordplay.
'no opening for' means to remove the first letter.
'beginner' becomes 'learner' (learner is a kind of beginner).
'learner' with its initial letter taken off is 'EARNER'.
'as' is the link.
(Other definitions for earner that I've seen before include "Job making money" , "Breadwinner" , "Coin collector" , "One who gets money for work" , "One in employment" .)