Crossword Genius

Cheap cheese for the quiet one, a copper (5,4)

Ross

I believe the answer is:

mouse trap

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'cheap' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'cheese for the quiet one a copper' is the wordplay.
'cheese' becomes 'tr' (I can't justify this - if you can you should believe this answer much more).
'for' says to put letters next to each other (I've seen this in other clues).
'the quiet one' becomes 'mouse' (I've seen this in another clue).
'copper' becomes 'p'.
'tr' put after 'mouse' is 'mousetr'.
'mousetr'+'a'+'p'='MOUSE-TRAP'

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I've seen this clue in the Sydney Morning Herald.
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