Something of a looker this particular Murdoch? (4)
I believe the answer is:
'something of a looker this particular murdoch?' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
This is all the clue.
Can you help me to learn more?
(Other definitions for iris that I've seen before include "Flag,flower and part of the eye" , "Bright flower or eye part" , "bloomer?" , "- - Murdoch, novelist" , "Nice flower or eye part" .)