Evil spirit moaned terribly (6)

I believe the answer is:

daemon

'evil spirit' is the definition.
(daemon is a kind of evil spirit)

'moaned terribly' is the wordplay.
'terribly' indicates an anagram.
'moaned' is an anagram of 'DAEMON'.

(Other definitions for daemon that I've seen before include "Evil spirit" , "guardian spirit" , "Spirit in ancient Greek belief" .)

I've seen this clue in The Telegraph.

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