atomic clock

noun

Synonyms of atomic clocknext
: 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)

Examples of atomic clock in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The development could help make optical atomic clocks smaller and more suitable for use outside laboratories. — Neetika Walter, Interesting Engineering, 17 Oct. 2026 Since the 1970s, leap seconds have also been doing the job of correcting the imbalance between astronomical time and the ultraprecise atomic clocks that now set the global standard. — Maureen O'Hare, CNN Money, 17 Oct. 2026 It’s calculated via a weighted average of the time according to atomic clocks around the world and disseminated by the BIPM. — Emma Gometz, Scientific American, 15 Oct. 2026 Quantum sensors provide atomic clocks and inertial tracking for submarines, aircraft, and satellites, while the same technology is used to find oil and gas deposits. — David S. Cohen, Foreign Affairs, 8 Oct. 2026 See All Example Sentences for atomic clock

Word History

First Known Use

1924, in the meaning defined above

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

Rhymes for atomic clock

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Browse Nearby Words

atomic bomb
atomic clock
atomic constant
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Cite this Entry

“Atomic clock.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic%20clock. Accessed 19 Oct. 2026.

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Kids Definition

atomic clock

noun
: 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

Thesaurus: All synonyms and antonyms for atomic clock

Britannica.com: Encyclopedia article about atomic clock

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