Definition of "baron"

There were a few exotics among them — some South American boys, sons of Argentine beef barons, one or two Russians, and even a Siamese prince, or someone who was described as a prince.

c. 1948, George Orwell, Such, Such Were the Joys

British journalists shun complete respectability, feeling a duty to be ready to savage the mighty, or rummage through their bins. Elsewhere in Europe, government contracts and subsidies ensure that press barons will only defy the mighty so far.

2013 August 10, Lexington, “Keeping the mighty honest”, in The Economist‎, volume 408, number 8848

The first thing a baron does is to accumulate a supply of tobacco. He spends every penny he can earn on laying it in […]

1960, Hugh J. Klare, Anatomy of Prison, page 33

Nevertheless, from my own agonies of the first few months, after which I did not miss smoking at all, I could appreciate the need of others. It was in this atmosphere of craving that the 'barons' thrived. Barons are prisoners who lend tobacco.

1961, Peter Baker, Time out of life, page 51

In British prisons tobacco still remains the gold standard which is made to back every transaction and promise. The official allowance is barely sufficient for individual smoking needs, but tobacco may expensively be borrowed or bought from a baron, possibly through his runner.

1980, Leonard Michaels, Christopher Ricks, The State of the Language, page 525

Such portentous appetites had Queequeg and Tashtego, that to fill out the vacancies made by the previous repast, often the pale Dough-Boy was fain to bring on a great baron of salt-junk, seemingly quarried out of the solid ox.

1851 November 14, Herman Melville, “chapter 34”, in Moby-Dick; or, The Whale, 1st American edition, New York, N.Y.: Harper & Brothers; London: Richard Bentley