Aha, see it’s become sensitivity (9)

I believe the answer is:

aesthesia

'sensitivity' is the definition.
(I've seen this in another clue)

'aha see it's become' is the wordplay.
'become' indicates anagramming the letters.
'aha'+'see'+'its'='ahaseeits'
'ahaseeits' with letters rearranged gives 'AESTHESIA'.

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

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