Approval as European joins up (6)
I believe the answer is:
esteem
'approval' is the definition.
(thesaurus)
'european joins up' is the wordplay.
'european' becomes 'E' (abbreviation e.g. EU).
'joins' becomes 'meets' (meeting is a kind of joining).
'up' is a reversal indicator (in down clue: letters go upwards).
'meets' written backwards gives 'steem'.
'e'+'steem'='ESTEEM'
'as' is the link.
(Other definitions for esteem that I've seen before include "Venerate" , "Admire - honour" , "Consider" , "Honour - regard" , "judge" .)