un·​ob·​serv·​able | \ ˌən-əb-ˈzər-və-bəl \

Definition of unobservable

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

Examples of unobservable in a Sentence

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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.

First Known Use of unobservable

1615, in the meaning defined above

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The first known use of unobservable was in 1615

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a servile follower or underling

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