"Tycoon" is a
folk spelling invented by American writers when they heard the fantastic stories brought back from
Japan by
travelers and
traders. A more acceptable spelling would be "Taikun," the
kanji for which comes out to something along the lines of "the big you."
The word entered the early American meme pool when these American journalists were trying to come up with new ways to attack steel barons and railbarons that were starting to manipulate the government by buying favors that would better their businesses.
The story went that the Emperor was supposed to be in charge of Japan, but, in reality, the Emperor had almost no power, and everything was run by the "Tycoons." Thus the term "Rail Road Tycoon" meant a plutocrat who bribed his way through the government and pulled the strings from behind the scenes.