Coat under slip taken down in error (8)
I believe the answer is:
misspelt
'taken down in error' is the definition.
'coat under slip' is the wordplay.
'coat' becomes 'pelt' (animal coat).
'under' means one lot of letters go next to another.
'slip' becomes 'miss'.
'pelt' put after 'miss' is 'MISSPELT'.
(Other definitions for misspelt that I've seen before include "having written words wrongly" , "like velvit?" , "literal?" , "badly written" , "at least one letter out" .)