Gross affluence meets demonstration stopping oil (11)

I believe the answer is:

greaseproof

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'gross affluence meets demonstration stopping oil' is the definition.
I can't tell whether this defines the answer.

'gross affluence meets demonstration' is the wordplay.
'gross' becomes 'gr' (abbreviation).
'affluence' becomes 'ease' (ease is a kind of affluence).
'meets' means one lot of letters go next to another.
'demonstration' becomes 'proof' (I've seen this before).
'gr'+'ease'+'proof'='GREASEPROOF'

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(Another definition for greaseproof that I've seen is " being resistant to fat".)

I've seen this clue in The Independent.

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