Releasing toilet pipe (7)

I believe the answer is:

loosing

'releasing' is the definition.
('loose' can be a synonym of 'release')

'toilet pipe' is the wordplay.
'toilet' becomes 'loo' (loo can informally mean a toilet).
'pipe' becomes 'sing' (pipe can mean to sing or chirp).
'loo'+'sing'='LOOSING'

I've seen this clue in The Guardian.

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