Consult the man with the whistle? (5)

I believe the answer is:

refer

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'consult' is the definition.
(thesaurus)

I cannot understand how the remainder of the clue works.

(Other definitions for refer that I've seen before include "Mention, cite" , "Freer (anag.)" , "Advert, cite" , "Send a patient to a specialist" , "Be relevant (to)" .)

I've seen this clue in the Evening Standard.

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