City subordinate to address filth in lucre? (7)

I believe the answer is:

launder

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'to address filth in lucre?' is the definition.
I can't tell whether this definition defines the answer.

'city subordinate' is the wordplay.
'city' becomes 'la' (Los Angeles).
'subordinate' becomes 'under' ('under' can be similar in meaning to 'subordinate').
'la'+'under'='LAUNDER'

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(Other definitions for launder that I've seen before include "Trough" , "Convert illegal funds into legal ones" , "Perhaps decriminalise" , "Wash and iron clothes etc" , "Wash and iron linen" .)

I've seen this clue in The Telegraph.

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