Prohibition affecting nobleman (5)

I believe the answer is:

baron

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'nobleman' is the definition.
(baron is a kind of nobleman)

I cannot understand how the rest of the clue works.

(Other definitions for baron that I've seen before include "Noble rank" , "captain of industry" , "Lowest rank of British peerage" , "Title of rank" , "Minor nobleman" .)

I've seen this clue in The Irish News.

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