Boy's name for a fish (3)

I believe the answer is:

ray

I believe this is a triple definition!

'boy's' is the first definition.

'name' is the second definition.

'for a fish' is the third definition.
(ray is a kind of fish)

(Other definitions for ray that I've seen before include "Flat fish or sun beam" , "Lindwall" , "A little light" , "bit of sunshine" , "Sunbeam or flat fish" .)

I've seen this clue in the Evening Standard.

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