Woman with capacity to be realistic (6)
I believe the answer is:
viable
'realistic' is the definition.
'woman with capacity' is the wordplay.
'woman' becomes 'vi' (short for Violet).
'with capacity' becomes 'able'.
'vi'+'able'='VIABLE'
'to be' is the link.
(Other definitions for viable that I've seen before include "Sound" , "Having a prospect of success" , "Workable" , "Practicable, able to be done successfully" , "Capable of life and growth" .)