Composer ignored by a novelist and painter (2,5)
I believe the answer is:
el greco
'painter' is the definition.
(nickname of Domenikos Theotokpoulos, 1541-1641)
'composer ignored by a novelist' is the wordplay.
'composer' becomes 'elgar' (Edward Elgar).
'ignored by' is a deletion indicator.
'novelist' becomes 'eco' (Umberto Eco).
'elgar' with 'a' removed is 'elgr'.
'elgr'+'eco'='EL GRECO'
'and' is the link.
(Other definitions for el greco that I've seen before include "Spanish painter, nicknamed for his place of birth" , "Domenikos Theotokopoulos" , "He painted" , "Sixteenth to seventeenth century Greek-born Spanish painter" , "Spanish painter born in Greece" .)