Cleaned the bad mess (6)
I believe the answer is:
bathed
'cleaned' is the definition.
(bathing is a kind of cleaning)
'the bad mess' is the wordplay.
'mess' is an anagram indicator.
'the'+'bad'='thebad'
'thebad' is an anagram of 'BATHED'.
(Another definition for bathed that I've seen is " Cleansed the body".)
I've seen this clue in the Evening Standard.
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