Criticism upsets Mabel (5)
I believe the answer is:
blame
'criticism' is the definition.
(blame is a kind of criticism)
'upsets mabel' is the wordplay.
'upsets' is an anagram indicator.
'mabel' anagrammed gives 'BLAME'.
(Other definitions for blame that I've seen before include "Accountability" , "Assign responsibility for misdeed" , "Accuse" , "Attribute fault or guilt to" , "Censure; culpability" .)