Mediterranean microstate (6)
I believe the answer is:
monaco
'mediterranean microstate' is the definition.
(I know that Monaco is a microstate)
This is the entire clue.
(Other definitions for monaco that I've seen before include "Oman Co. (anag)" , "Med principality" , "Small European principality" , "Constitutional monarchy on the French Riviera" , "Southwest European principality" .)