Fit pipe into empty cistern that's been carefully selected (10)

I believe the answer is:

wellchosen

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'fit pipe into empty cistern that's been' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'carefully selected' is the wordplay.
'carefully' becomes 'well' (doing something well can mean doing it carefully).
'selected' becomes 'chosen' (similar in meaning).
'well'+'chosen'='WELLCHOSEN'

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I've seen this clue in The Irish Times.

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