The washerwoman? Not she! (3)
I believe the answer is:
her
'she' is the definition.
(I've seen this in other clues)
'the washerwoman? not' is the wordplay.
'HER' is hidden within the letters.
But, I'm not sure how the hidden word is indicated.
Can you help me to learn more?
(Other definitions for her that I've seen before include "Belonging to the woman" , "She, objectively" , "Belonging to a female" , "Pronoun used of ship" , "That lady" .)