Manner is unfriendly about European average (9)
I believe the answer is:
demeanour
'manner' is the definition.
The answer and definition can be both human attributes as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'unfriendly about european average' is the wordplay.
'unfriendly' becomes 'dour'.
'about' is an insertion indicator.
'european' becomes 'E' (abbreviation e.g. EU).
'average' becomes 'mean' (type of average).
'e'+'mean'='emean'
'dour' enclosing 'emean' is 'DEMEANOUR'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for demeanour that I've seen before include "Manner of behaving towards others" , "Look" , "Outward bearing" , "Conduct" , "Appearance and attitude" .)