Foucault pendulum

noun

Fou·​cault pendulum ˌfü-ˈkō- How to pronounce Foucault pendulum (audio)
: a freely swinging pendulum that consists of a heavy weight hung by a long wire and that swings in a constant direction which appears to change showing that the earth rotates

Examples of Foucault pendulum in a Sentence

Recent Examples on the Web This is often called a Foucault pendulum (named after Leo Foucault). Rhett Allain, WIRED, 26 Jan. 2024 The perpetually swinging Foucault pendulum in the lobby hangs still. David L. Coddon, San Diego Union-Tribune, 25 Feb. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'Foucault pendulum.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

J. B. L. Foucault

First Known Use

1931, in the meaning defined above

Time Traveler
The first known use of Foucault pendulum was in 1931

Dictionary Entries Near Foucault pendulum

Cite this Entry

“Foucault pendulum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Foucault%20pendulum. Accessed 19 Apr. 2024.

Kids Definition

Foucault pendulum

noun
Fou·​cault pendulum ˌfü-ˌkō- How to pronounce Foucault pendulum (audio)
: a device that consists of a heavy weight hung by a long wire and that swings in a constant direction which appears to change showing that the earth rotates

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