A European shiner! (6)
I believe the answer is:
polish
This clue might be a double definition.
'a european' is the first definition.
(I've seen this before)
'shiner' is the second definition.
The answer and definition can be both states of affairs as well as being singular nouns.
Maybe you can see an association between them that I don't see?
Can you help me to learn more?
(Other definitions for polish that I've seen before include "Shine up the nationality" , "Shine up in Warsaw" , "Give shine to" , "See 1" , "Rub - European" .)