Sheen’s European? (6)
I believe the answer is:
polish
This clue is a double definition.
'sheen's' is the first definition.
(thesaurus)
'european?' is the second definition.
(I've seen this before)
(Other definitions for polish that I've seen before include "European language - refinement" , "Shine up the nationality" , "Beeswax, for example" , "Gloss - refinement" , "'Buff, burnish (6)'" .)