tycoon: [19] Japanese taikun was a title used for the military commander or shogun of Japan, particularly by his supporters when addressing foreigners, in the attempt to convey the impression that he was more powerful and important than the emperor. For it meant literally ‘great prince, emperor’. It was borrowed from ancient Chinese t’ai kiuən ‘emperor’, a compound formed from t’ai ‘great’ and kiuən ‘prince’. English acquired it in the 1850s, and it began to be used more generally for a ‘highranking personage’ in the USA soon afterwards. The specific application to businessmen seems to have evolved after World War I.
1857, title given by foreigners to the shogun of Japan (said to have been used by his supporters when addressing foreigners, as an attempt to convey that the shogun was more important than the emperor), from Japanese taikun "great lord or prince," from Chinese tai "great" + kiun "lord." Transferred meaning "important person" is attested from 1861, in reference to U.S. president Abraham Lincoln (in the diary of his secretary, John Hay); specific application to "wealthy and powerful businessman" is post-World War I.
