Hold back an expression of disapproval in play (4-1-3)

I believe the answer is:

peek-a-boo

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'play' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'hold back an expression of disapproval' is the wordplay.
'hold' becomes 'keep' (keeping is a kind of holding).
'back' is a reversal indicator.
'an' becomes 'a'.
'expression of disapproval' becomes 'boo' (as in a crowd booing).
'keep' in reverse letter order is 'peek'.
'peek'+'a'+'boo'='PEEK-A-BOO'

'in' is the link.

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I've seen this clue in The Globe and Mail.

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