Master of some art (7)
I believe the answer is:
maestro
'master' is the definition.
(synonyms)
'of some art' is the wordplay.
'of' is an anagram indicator (the answer comes from or \'of\' the letters).
'some'+'art'='someart'
'someart' is an anagram of 'MAESTRO'.
(Other definitions for maestro that I've seen before include "ace" , "Expert musician" , "Highly skilled musician" , "Distinguished musician - most are (anag)" , "Eminent conductor or composer" .)