atomic clock


: a precision clock that depends for its operation on an electrical oscillator regulated by the natural vibration frequencies of an atomic system (such as a beam of cesium atoms)

Example Sentences

Recent Examples on the Web By 1949, the first atomic clock was up and running. Tom Vanderbilt, Harper’s Magazine , 13 Mar. 2023 But instead of figuring out a unique time zone for the station, scientists rely on Coordinated Universal Time, or UTC, which is reportedly based on atomic clocks. Caitlin Mcfall, Fox News, 1 Mar. 2023 The second is defined by a process that occurs in the nucleus of a cesium-155 atom—a process that atomic clocks can calculate with stunning accuracy. Rahul Rao, Popular Science, 20 Feb. 2023 The sensors’ accuracy at measuring time makes atomic clocks inside many GPS satellites tick–literally. Kristin M. Gilkes, Fortune, 18 Feb. 2023 Technically, the ideal measure of time would come from an atomic clock in the vacuum of space, where there’s essentially no gravity. WIRED, 28 Mar. 2023 An atomic clock based on a fountain of atoms. Kevin Purdy, Ars Technica, 3 Aug. 2022 Using data from the International Earth Rotation and Reference Systems Service, says 2020 boasted 28 of the world’s shortest days on record since the introduction of the atomic clock in the 1960s made the measurement more scientifically accurate. Tim Newcomb, Popular Mechanics, 1 Aug. 2022 In quantum mechanics, the concept of time itself is deeply complicated, said Jun Ye, a physicist who created the world’s most precise atomic clock, a project of the National Institute of Standards and Technology and the University of Colorado Boulder. New York Times, 1 Jan. 2022 See More

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

Word History

First Known Use

1924, in the meaning defined above

Time Traveler
The first known use of atomic clock was in 1924

Dictionary Entries Near atomic clock

Cite this Entry

“Atomic clock.” Dictionary, Merriam-Webster, Accessed 6 Jun. 2023.

Kids Definition

atomic clock

: an extremely exact clock that depends for its operation on the natural vibrations of atoms (as of cesium)

More from Merriam-Webster on atomic clock

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