Most active local objector finally failing in case (8)

I believe the answer is:

nimblest

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'most active local objector finally failing in case' is the definition.
I can't tell whether this defines the answer.

'most active local objector' is the wordplay.
'most' means to remove the last letter.
'active' becomes 'nimble' (similar in meaning).
'local objector' becomes 'est' (I can't explain this - if you can you should believe this answer much more).
'nimble' with its final letter taken away is 'nimbl'.
'nimbl'+'est'='NIMBLEST'

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(Another definition for nimblest that I've seen is " Most agile, mentally of physically".)

I've seen this clue in The Times.

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