Masseuse character is OK (11)

I believe the answer is:

rubberstamp

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'ok' is the definition.
Although both the answer and definition are verbs in their base form, I cannot understand how one could define the other.

'masseuse character' is the wordplay.
'masseuse' becomes 'rubber'.
'character' becomes 'stamp' (I've seen this before).
'rubber'+'stamp'='RUBBERSTAMP'

'is' acts as a link.

Can you help me to learn more?

I've seen this clue in The Times.

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