Message sensibly conveyed in this bottle (5)

I believe the answer is:

nerve

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'this bottle' is the definition.
(I've seen this before)

I can't explain the rest of the clue.

(Other definitions for nerve that I've seen before include "Courage to carry on" , "Fearlessness" , "Impudence; courage" , "Cord that carries instructions from brain to body" , "Bundle of fibres in the body (5)" .)

I've seen this clue in The Times and The Sun.

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