"A Pure Woman" of an 1891 novel (4)
I believe the answer is:
tess
'a pure woman of an 1891 novel' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tess that I've seen before include "Hardy's Durbeyfield heroine" , "20 heroine" , "Lady" , "- - of the d'Urbervilles" , "tragic heroine" .)