1 : a Japanese sect of Mahayana Buddhism that aims at enlightenment by direct intuition through meditation

2 or zen : a state of calm attentiveness in which one's actions are guided by intuition rather than by conscious effort Perhaps that is the zen of gardeningyou become one with the plants, lost in the rhythm of the tasks at hand. Irene Virag

1 : of, relating to, or associated with Zen Buddhism a Zen monk/priest/master

2a : suggestive of the teachings or practice of Zen Buddhism Paddling, itself, is a Zen art: Anyone can do it, yet you can spend a lifetime perfecting it. Jim Albrecht

b : having or showing qualities (such as meditative calmness and an attitude of acceptance) popularly associated with practitioners of Zen Buddhism "I hate to use this word, but Owen is very 'Zen,'" said Rita Nagel, a vice president at Goldman, Sachs. "When some traders start losing money they get nervous. Owen stays very relaxed."

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Zen | Definition of Zen by Merriam-Webster