Number to push out of order for big meal (4,2)

I believe the answer is:

nosh up

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'big meal' is the definition.
'nosh-up' can be an answer for 'meal' (nosh-up is a kind of meal). I'm not sure about the 'big' bit.

'number to push out of order' is the wordplay.
'number' becomes 'no' (abbreviation).
'to' says to put letters next to each other.
'out of order' indicates an anagram.
'push' is an anagram of 'shup'.
'no'+'shup'='NOSH-UP'

'for' is the link.

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I've seen this clue in The Daily Express.

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