Part of the eye around the pupil (4)
I believe the answer is:
iris
'part of the eye around the pupil' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for iris that I've seen before include "Flag or flower in the eye" , "Murdoch in writing" , "may open up in camera" , "Rainbow - flag" , "- - Murdoch, novelist" .)