Expert fulfilled (12)
I believe the answer is:
accomplished
I believe this clue is a double definition.
'expert' is the first definition.
(synonyms)
'fulfilled' is the second definition.
('accomplish' can be a synonym of 'fulfil')
(Other definitions for accomplished that I've seen before include "Talented - performed" , "Professional" , "Completed; skilful" , "Highly proficient" , "Done - with a high degree of skill" .)