Refinements that used to go with smart shirts? (8)
I believe the answer is:
niceties
'refinements' is the definition.
('nicety' can be a synonym of 'refinement')
I cannot understand how the rest of the clue works.
(Other definitions for niceties that I've seen before include "Shades" , "refinement" , "delicacies" , "Fine points" , "Delicacy" .)