un·​ob·​serv·​able | \ ˌən-əb-ˈzər-və-bəl How to pronounce unobservable (audio) \

Definition of unobservable

: incapable of being observed : not observable particles so small that they are unobservable

Examples of unobservable in a Sentence

Recent Examples on the Web

Here’s a quantum analogy: The Sleeping Beauty problem is like an unobservable particle in a quantum superposition of 50 percent H and 50 percent T among the ensemble of puzzle enthusiasts. Quanta Magazine, "Solution: ‘Sleeping Beauty’s Dilemma’," 29 Jan. 2016 Their private emotional lives are unobservable to us. Samantha Boardman, Marie Claire, "You Aren't the Only One with Duck Syndrome," 30 Apr. 2019 Understanding how to glean this unobservable rate is critical to setting Fed interest-rate policy. Nick Timiraos, WSJ, "New York Fed Eyes John Williams as Its Next Leader," 25 Mar. 2018 Zwicky had concluded that some type of massive, unobservable substance was lending gravitational heft to the cluster and helping to keep the thing intact. Nadia Drake, National Geographic, "Vera Rubin, Pioneering Astronomer, Dies at 88," 27 Dec. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unobservable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unobservable

1615, in the meaning defined above

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Statistics for unobservable

Last Updated

27 Jun 2019

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Time Traveler for unobservable

The first known use of unobservable was in 1615

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Comments on unobservable

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a period when something is suspended

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