Fish out of a can (4)

I believe the answer is:

sild

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

I cannot understand how the remainder of the clue works.

(Other definitions for sild that I've seen before include "Small herring" , "Young herring" , "young swimmers" , "Young fish" .)

I've seen this clue in the Evening Standard.

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