A bit of an eye for a girl (4)
I believe the answer is:
iris
This clue is a double definition.
'a bit of an eye' is the first definition.
('iris' is part of 'eye')
'a girl' is the second definition.
'for' is the link.
(Other definitions for iris that I've seen before include "- - Murdoch, novelist" , "bloomer?" , "Flowers in the eye?" , "Eye part or pretty flower" , "Ms Murdoch" .)