European national flag is intact (6)
I believe the answer is:
entire
'intact' is the definition.
(synonyms)
'european national flag' is the wordplay.
'european' becomes 'E' (abbreviation e.g. EU).
'national' becomes 'n' (abbreviation listed in Chambers).
'flag' becomes 'tire' (I've seen this before).
'e'+'n'+'tire'='ENTIRE'
'is' acts as a link.
(Other definitions for entire that I've seen before include "excluding nothing" , "Utter" , "Unharmed - total" , "With no part left out" , "everything" .)