Crossword Genius

Down whiskey in front of healthy swimmer (4,5)

Ross

I believe the answer is:

blue whale

I'm a little stuck... Click here to teach me more about this clue!

'swimmer' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.

'down whiskey in front of healthy' is the wordplay.
'down' becomes 'blue' (both can mean sad).
'whiskey' becomes 'W' (phonetic alphabet: alpha, bravo, charlie etc.).
'in front of' means one lot of letters go next to another (some letters go in front of others).
'healthy' becomes 'hale' (hale can mean fit and healthy).
'blue'+'w'+'hale'='BLUE WHALE'

Can you help me to learn more?

(Other definitions for blue whale that I've seen before include "World's largest mammal" , "Largest living animal" , "World's largest animal" , "there's nothing bigger" .)

I've seen this clue in The Telegraph.
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