Coward put her in a double-negative (3-4)

I believe the answer is:

non-hero

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'coward' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'her in a double-negative' is the wordplay.
'in' is an insertion indicator.
'a double negative' becomes 'nono' (I've seen this in another clue).
'her' going inside 'nono' is 'NON-HERO'.

'put' is the link.

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I've seen this clue in the Sydney Morning Herald.

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