Comedian bad? Diabolical! (8)

I believe the answer is:

demoniac

'diabolical' is the definition.
(thesaurus)

'comedian bad?' is the wordplay.
'bad?' is an anagram indicator (I've seen 'bad' mean this).
'comedian' with letters rearranged gives 'DEMONIAC'.

(Other definitions for demoniac that I've seen before include "Comedian of frenzied sort" , "Comedian of develish kind" , "Person possessed by an evil spirit" , "Diabolical" , "man possessed" .)

I've seen this clue in The Telegraph.

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