Women who help to make men unselfish (4)
I believe the answer is:
nuns
'women' is the definition.
(I have seen 'Retired women' mean 'nuns' so perhaps 'women' could also mean 'nuns')
'help to make men unselfish' is the wordplay.
'help to make' indicates the answer is hidden within the clue (I've seen 'helping to make' mean this).
'NUNS' is hidden within 'men unselfish'.
'who' acts as a link.
(Other definitions for nuns that I've seen before include "Sisters in order" , "women in order" , "Holy sisters" , "Religious community members" , "Women in religious vocations" .)