Fish stew initially a hit? Nonsense (10)

I believe the answer is:

codswallop

'nonsense' is the definition.
(I know that nonsense can be written as codswallop)

'fish stew initially a hit?' is the wordplay.
'fish' becomes 'cod' (type of fish).
'initially' suggests taking the first letters.
'a hit?' becomes 'wallop' (I've seen this before).
The initial letter of 'stew' is 's'.
'cod'+'s'+'wallop'='CODSWALLOP'

(Other definitions for codswallop that I've seen before include "Nonsense (colloq.)" , "tripe" , "Rubbish!" , "moonshine" , "Baloney" .)

I've seen this clue in The Daily Express.

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