Measured partly to be certain (4)

I believe the answer is:

sure

'certain' is the definition.
(synonyms)

'measured partly' is the wordplay.
'partly' says the answer is hidden in the clue.
'SURE' is hidden within 'measured'.

'to be' acts as a link.

(Other definitions for sure that I've seen before include "Definite" , "Undoubtedly true" , "Certain to be a ruse" , "of course" , "Completely certain" .)

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

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