Capital of Wales (7)
I believe the answer is:
cardiff
'capital of wales' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for cardiff that I've seen before include "Welsh city" , "Welsh capital" , "Place in Wales" , "City on the Taff" , "European capital, birthplace of Roald Dahl" .)