Unlikely to give up precautions, I suspect (12)

I believe the answer is:

pertinacious

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'unlikely to give up' is the definition.
I can't judge whether this defines the answer.

'precautions i suspect' is the wordplay.
'suspect' indicates an anagram (a suspicious or unusual spelling).
'precautions'+'i'='precautionsi'
'precautionsi' anagrammed gives 'PERTINACIOUS'.

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I've seen this clue in The Times.

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