Dianne mistaken for another woman (6)
I believe the answer is:
nadine
'another woman' is the definition.
'Nadine' can be an answer for 'woman'. I'm unsure of the 'another' bit.
'dianne mistaken' is the wordplay.
'mistaken' indicates anagramming the letters.
'dianne' anagrammed gives 'NADINE'.
'for' is the link.
(Other definitions for nadine that I've seen before include "Woman" , "Girl's name; Dianne (anag.)" , "French girl" , "South African writer" .)