Woman’s death overcoming one (4)
I believe the answer is:
enid
'woman's' is the definition.
(woman's name)
'death overcoming one' is the wordplay.
'death' becomes 'end' (synonyms).
'overcoming' is an insertion indicator.
'one' becomes 'i' (Roman numeral).
'end' going around 'i' is 'ENID'.
(Other definitions for enid that I've seen before include "- Blyton, children's writer" , "W - - Blyton" , "Arthurian wife" , "Dine out on this girl's name also" , "Geraint's loved one" .)