Astounded doctor mocked bags (10)
I believe the answer is:
gobsmacked
'astounded' is the definition.
(I've seen this before)
'doctor mocked bags' is the wordplay.
'doctor' is an anagram indicator.
'mocked'+'bags'='mockedbags'
'mockedbags' anagrammed gives 'GOBSMACKED'.
(Other definitions for gobsmacked that I've seen before include "Dumbfounded" , "shocked" , "utterly astonished" , "bowled over" , "Astounded" .)