Some relief a moussaka is notable (6)
I believe the answer is:
famous
'notable' is the definition.
('famous' can be a synonym of 'notable')
'some relief a moussaka' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'FAMOUS' is hidden within 'relief a moussaka'.
'is' acts as a link.
(Other definitions for famous that I've seen before include "Widely-known" , "Known to very many people" , "Known-of widely" , "Renowned, noted" , "Well known" .)