Nick, we hear, and John providing fish (9)

I believe the answer is:

steelhead

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'fish' is the definition.
(thesaurus)

'nick we hear and john providing' is the wordplay.
'nick' becomes 'steal' (I've seen this before).
'we hear' indicates a 'sounds like' (homophone) clue.
'and' is a charade indicator (letters next to each other).
'john providing' becomes 'head' (I can't justify this - if you can you should give a lot more credence to this answer).
'steal' sounds like 'steel'.
'steel'+'head'='STEELHEAD'

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I've seen this clue in The Times.

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