Pedants possibly man rebuffed in places (7)
I believe the answer is:
purists
'pedants' is the definition.
(I know this)
'man rebuffed in places' is the wordplay.
'man' becomes 'sir' (sir is a kind of man).
'rebuffed' shows that the letters should be reversed in order.
'in' is an insertion indicator.
'places' becomes 'puts' ('put' can be a synonym of 'place').
'sir' in reverse letter order is 'ris'.
'ris' put within 'puts' is 'PURISTS'.
'possibly' acts as a link.
(Other definitions for purists that I've seen before include "Sticklers for traditional rules" , "Pedantic folk" , "pedants" , "fastidious types" .)