Bishop with skill, fine composer (6)
I believe the answer is:
bartok
'composer' is the definition.
(I've seen this before)
'bishop with skill fine' is the wordplay.
'bishop' becomes 'b' (abbreviation used in chess).
'with' means one lot of letters go next to another.
'skill' becomes 'art' (I've seen this before).
'fine' becomes 'ok' (synonyms).
'b'+'art'+'ok'='BARTOK'
(Other definitions for bartok that I've seen before include "Bela -, nineteenth and twentieth century Hungarian composer" , "Hungarian-born composer, d. 1945" , "Bela -, Hung. composer" , "Bark to attract great Hungarian composer" , "Hungarian composer and pianist, d. 1945" .)