Ch'osŏn (Korean). A term which can refer either to Korea as a whole, or to a particular period in Korean history from 1392 to 1909 during which Buddhism was actively suppressed. This was a period of persecution and declining influence for Buddhism that lasted 518 years. As each ruler ascended the throne, stronger and stronger anti-Buddhist measures went into effect. These included a halt to new temple construction; restrictions on ordinations; the actual closing of monasteries in urban areas and their gradual restriction to isolated mountain sites; and a proscription on travel by monks and nuns.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)