With which to see flower (4)
I believe the answer is:
iris
I believe this clue is a double definition.
'with which to see' is the first definition.
(part of the eye)
'flower' is the second definition.
(iris is a type of flower)
(Other definitions for iris that I've seen before include "bit of mince pie" , "Ms Murdoch" , "Flag,flower and part of the eye" , "Flag or flower in the eye" , "Flower and eye membrane" .)