Geraint's lady (4)
I believe the answer is:
enid
'geraint's lady' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for enid that I've seen before include "W - - Blyton" , "Arthurian wife" , "Miss Blyton" , "Dine with this girl" , "Woman" .)