Artist unknown in part of India (4)
I believe the answer is:
goya
'artist' is the definition.
(Francisco Goya)
'unknown in part of india' is the wordplay.
'unknown' becomes 'y' (algebra).
'in' means one lot of letters goes inside another.
'part of india' becomes 'goa' (Goa is an Indian state).
'y' put within 'goa' is 'GOYA'.
(Other definitions for goya that I've seen before include "Eighteenth to nineteenth century Spanish artist" , "Spanish painter (Los Caprichos)" , "Artist, died at Bordeaux, 1828" , "Francesco de ---, Sp. court painter" , "Francisco de ---- (1746-1828), Spanish painter of portraits" .)