Says one realises it's the front (4)

I believe the answer is:

nose

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'the front' is the definition.
(nose is a kind of front)

I don't understand the rest of the clue.

(Other definitions for nose that I've seen before include "Olfactory organ" , "Facial part" , "Hooter" , "Cyrano's large feature" , "Aroma of wine" .)

I've seen this clue in the Evening Standard.

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