Spat onion out.Insecticide! (3,6)

I believe the answer is:

ant poison

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'insecticide' is the definition.
I know nothing about this answer so I can't tell whether this works.

'spat onion out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'spat'+'onion'='spatonion'
'spatonion' anagrammed gives 'ANT POISON'.

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

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