Check polish again (6)
I believe the answer is:
rebuff
I believe this is a double definition.
'check' is the first definition.
(I've seen this before)
'polish again' is the second definition.
('buff' is an answer for 'polish' so perhaps 'rebuff' is OK for 'polish again')
(Other definitions for rebuff that I've seen before include "Spurn, snub" , "Cold-shoulder" , "Deliberate discourteous act" , "Check" , "Blunt rejection" .)