Feedback certain, so dealt with (9)

I believe the answer is:

reactions

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'feedback certain so dealt with' is the definition.
I can't tell whether this defines the answer.

'certain so dealt with' is the wordplay.
'dealt with' indicates anagramming the letters.
'certain'+'so'='certainso'
'certainso' with letters rearranged gives 'REACTIONS'.

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(Other definitions for reactions that I've seen before include "Takes" , "What you may get with chemicals" , "Newton's law of motion says all actions have them" , "Mental or physical responses" , "Responses, chemical perhaps" .)

I've seen this clue in The Daily Express.

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