The capital of Austria (6)
I believe the answer is:
vienna
'the capital of austria' is the definition.
('Vienna' can be a synonym of 'capital of austria')
This is all the clue.
(Other definitions for vienna that I've seen before include "European city for New Year's Day concert" , "City of Strauss and the waltz" , "Austria's capital city" , "somewhere in Austria" , "Capital on the Danube Canal" .)