Indifferent to criticism (5-7)
I believe the answer is:
thick-skinned
'indifferent to criticism' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for thick-skinned that I've seen before include "Pretty impermeable to criticism" , "Not easily hurt, upset" , "Insensitive" , "Indifferent to criticism" .)