Established already that publicity caused editor, twice, to receive fine (10)

I believe the answer is:

predefined

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'established already that publicity' is the definition.
I can't tell whether this definition defines the answer.

'caused editor twice to receive fine' is the wordplay.
'caused' becomes 'pr' (I am not sure about this - if you are sure you should believe this answer much more).
'editor' becomes 'ed' (abbreviation).
'twice' indicates the doubling of some letters.
'to receive' indicates putting letters inside.
'ed' duplicated is 'eded'.
'eded' enclosing 'fine' is 'edefined'.
'pr'+'edefined'='PREDEFINED'

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I've seen this clue in The Irish Times.

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