Money that hasn't been laundered? (6,5)

I believe the answer is:

filthy lucre

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'money' is the definition.
(I've seen this before)

I don't understand how the remainder of the clue works.

(Other definitions for filthy lucre that I've seen before include "Money, disparagingly" , "Sordid gain" , "Ill-gotten wealth" , "Dishonourably obtained money (colloq.)" .)

I've seen this clue in the Evening Standard.

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