Feature includes a work of the composer (6)
I believe the answer is:
chopin
'the composer' is the definition.
(Frederic Chopin)
'feature includes a work' is the wordplay.
'feature' becomes 'chin' (chin is a kind of feature).
'includes' means one lot of letters goes inside another.
'a work' becomes 'op' (abbreviation for opus).
'chin' placed around 'op' is 'CHOPIN'.
'of' acts as a link.
(Other definitions for chopin that I've seen before include "Polish virtuoso composer" , "Polish composer who had affair with George Sand" , "his writing noted" , "Polish composer of much piano music" , "Polish composer and pianist, d. 1849" .)