Pronunciation: (zen),[key] —n. 1. Chinese, Ch'an.Buddhism.a Mahayana movement, introduced into China in the 6th century a.d.and into Japan in the 12th century, that emphasizes enlightenment for the student by the most direct possible means, accepting formal studies and observances only when they form part of such means. Cf. koan, mondo. 2. the discipline and practice of this sect. Also calledZen Buddhism.