Deregulation left big airlines in trouble (12)

I believe the answer is:

liberalising

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'deregulation left big airlines in trouble' is the definition.
I can't tell whether this definition defines the answer.

'left big airlines in trouble' is the wordplay.
'left' becomes 'l' (common abbreviation).
'in trouble' indicates anagramming the letters.
'big'+'airlines'='bigairlines'
'bigairlines' with letters rearranged gives 'iberalising'.
'l'+'iberalising'='LIBERALISING'

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I've seen this clue in The Guardian.

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