Scoffing inside or out (8)
I believe the answer is:
derision
'scoffing' is the definition.
(I know that scoffing can be written as derision)
'inside or out' is the wordplay.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
'inside'+'or'='insideor'
'insideor' is an anagram of 'DERISION'.
(Other definitions for derision that I've seen before include "Contemptuous mockery" , "'Ridicule, contempt (8)'" , "Contemptuous ridicule" , "Mockery, ridicule" , "Ironside (anag) - mockery" .)