A puzzling, often paradoxical statement or story, used in Zen Buddhism as an aid to meditation and a means of gaining spiritual awakening.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "koan" in a sentence
"The Zen scholar and teacher, Daisetz Suzuki (1870 - 1966), once explained that the origin of the term koan was a kind of certifying document that, in ancient times, was used to test one's understanding of Zen."
"4 The koan is the principal form of meditation practiced by the Rinzai sect."
"A koan is a Zen riddle, the answer to which—if, in fact, there is an answer—is largely immaterial."