Well-turned-out son right to wear brownish-purple (6)
I believe the answer is:
spruce
'well-turned-out' is the definition.
(spruce can mean smart-looking)
'son right to wear brownish-purple' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'right' becomes 'r' (abbreviation).
'to wear' means one lot of letters goes inside another (to wear something is to be covered up by it).
'brownish purple' becomes 'puce' (I've seen this before).
'r' placed inside 'puce' is 'pruce'.
's'+'pruce'='SPRUCE'
(Other definitions for spruce that I've seen before include "Neat and smart like pine tree" , "Christmas tree, perhaps" , "Coniferous tree" , "Natty as a tree" , "Elegant" .)