Utterly audible! (6)

I believe the answer is:

spoken

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'audible' is the definition.
Both the answer and definition are adjectives. Maybe there's a link between them I don't understand?

I don't understand the remainder of the clue.

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(Other definitions for spoken that I've seen before include "Verbalised" , "Oral" , "Said" , "Declared" , "Uttered through the medium of speech" .)

I've seen this clue in the Evening Standard.

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