The word tycoon is derived from the Japanese word taikun (大君?), which means "great lord," and it was used as a title for the shogun.
The word entered the English language in 1857 with the return of Commodore Perry to the United States. U.S. President Abraham Lincoln was humorously referred to as the Tycoon by his aides.
The term spread to the business community, where it has been used ever since.Source
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