Crossword Genius

Receipt: reduced margin on it (5,4)

Ross

I believe the answer is:

sales slip

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'it' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'receipt reduced margin on' is the wordplay.
'receipt' becomes 'slip' (I've seen this in another clue).
'reduced margin' becomes 'sales' (I am not sure about this - if you are sure you should believe this answer much more).
'on' says to put letters next to each other.
'slip' put after 'sales' is 'SALES SLIP'.

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I've seen this clue in The Guardian.
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