Popular viewpoint, for example (8)
I believe the answer is:
'example' is the definition.
('instance' can be a synonym of 'example')
'popular viewpoint' is the wordplay.
'popular' becomes 'in'.
'viewpoint' becomes 'stance' (I've seen this before).
'for' is the link.
(Other definitions for instance that I've seen before include "Occasion" , "Specimen" , "Case - isn't acne (anag)" , "Particular case; cite" , "Canniest (anag) - occurrence" .)