Artist is overcome by shock assessment (9)
I believe the answer is:
appraisal
'assessment' is the definition.
('appraisal' can be a synonym of 'assessment')
'artist is overcome by shock' is the wordplay.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'overcome by' indicates putting letters inside.
'shock' becomes 'appal' ('appal' can be a synonym of 'shock').
'ra'+'is'='rais'
'rais' placed inside 'appal' is 'APPRAISAL'.
(Other definitions for appraisal that I've seen before include "Evaluation - papal airs (anag)" , "rating" , "judgement" , "judgment" , "Evaluation - price survey" .)