In retrospect some boffin won erudite fame (6)
I believe the answer is:
renown
'fame' is the definition.
('renown' can be a synonym of 'fame')
'in retrospect some boffin won erudite' is the wordplay.
'in retrospect' is a reversal indicator.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'nwoner' is hidden within 'boffin won erudite'.
'nwoner' in reverse letter order is 'RENOWN'.
(Other definitions for renown that I've seen before include "Fame, respect" , "High reputation, fame" , "Celebrity, fame" , "High repute" , "Good reputation" .)