Noblemen harm wine (9)

I believe the answer is:

margraves

'noblemen' is the definition.
(margrave is a kind of nobleman)

'harm wine' is the wordplay.
'harm' becomes 'mar' (I've seen this before).
'wine' becomes 'graves' (left bank subregion of Bordeaux in France).
'mar'+'graves'='MARGRAVES'

(Other definitions for margraves that I've seen before include "aristocrats abroad" , "Noblemen" .)

I've seen this clue in The Independent.

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