Silly coot indicating eight (4)

I believe the answer is:

octo

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'eight' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'silly coot' is the wordplay.
'silly' indicates anagramming the letters.
'coot' anagrammed gives 'OCTO'.

'indicating' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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