Noises lose their third snouts (5)

I believe the answer is:

noses

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

'snouts' is the definition.
(I've seen this in another clue)

I don't understand how the remainder of the clue works.

(Other definitions for noses that I've seen before include "Beaks, conks" , "Proboscises" , "Schnozzles" , "Examines or detects by smelling" , "Snouts" .)

I've seen this clue in the Sydney Morning Herald.

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