koan

American  

[koh-ahn] / ˈkoʊ ɑn /

noun

Zen.

koans plural

1. a nonsensical or paradoxical question to a student for which an answer is demanded, the stress of meditation on the question often being illuminating.

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koan British  

/ ˈkəʊæn /

noun

1. (in Zen Buddhism) a problem or riddle that admits no logical solution

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Etymology

Origin of koan

1945–50; < Japanese kōan, earlier koũ-an < Middle Chinese, equivalent to Chinese gōngàn public proposal

Explanation

In Zen Buddhism, a koan is a surprising and often perplexing phrase that's used as a meditation tool. A well-known koan is "What is the sound of one hand clapping?" It's common in Zen Buddhist training for a teacher to present a koan to a student, often in the form of a question. Because of their paradoxical nature, koans are nearly impossible to answer, and students are expected to "sit with" them while meditating. Ideally, the koan eventually leads to enlightenment — and at the very least, it challenges the mind. The Japanese koān means "public matter for thought."

Example Sentences

It sounds like a koan but isn’t that far from reality.

From Slate • Mar. 18, 2026

Disentangling the way we perceive silence is like a Zen koan for neuroscientists—they must literally confront the sound of one hand clapping.

From Scientific American • Jul. 10, 2023

Altman's early question to Kornfield, akin to a Zen koan, served as a meditation for the two techno-spiritualists on stage, transcending rational thought to confront the central paradox of AI: How will we know?

From Salon • May 21, 2023

After all, its title is a Zen koan unto itself: “It Is What It Is.”

From Washington Post • Mar. 26, 2020

I bet if I did, he’d suggest meditation or come out with some Zen koan to counteract it.

From "Please Ignore Vera Dietz" by A.S. King