Clone data - terribly unreliable (9)

I believe the answer is:

anecdotal

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'unreliable' is the definition.
Both the answer and definition are adjectives. Perhaps they are linked in a way I don't understand?

'clone data terribly' is the wordplay.
'terribly' indicates an anagram.
'clone'+'data'='clonedata'
'clonedata' anagrammed gives 'ANECDOTAL'.

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(Other definitions for anecdotal that I've seen before include "Like some amusing stories" , "Like a story" , "Not supported by reliable facts" , "according to report" , "(Of an account) not necessarily true or reliable" .)

I've seen this clue in The Daily Express.

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