Crossword Genius

Fish had to go in front of weed (7)

Ross

I believe the answer is:

haddock

'fish' is the definition.
(haddock is a kind of fish)

'had to go in front of weed' is the wordplay.
'to go in front of' is a charade indicator (letters next to each other).
'weed' becomes 'dock' (type of weed).
'had'+'dock'='HADDOCK'

(Other definitions for haddock that I've seen before include "Fish similar to but smaller than cod" , "Cod-like fish" , "Edible fish like small cod" , "Swimmer" , "Popular food fish" .)

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