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
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Using this energy to calibrate a clock, like atomic clocks do, does not come without consequence, though. Andrei Derevianko, The Conversation, 14 Apr. 2026 To help overcome this issue, modern submarines use something called atomic clocks, which are extremely accurate timekeeping pieces. Christopher McFadden, Interesting Engineering, 12 Apr. 2026 From tabletop experiments to atomic clocks to celestial mechanics to gravitational lensing to the formation of the great cosmic web, its success rate is 100%. Big Think, 24 Mar. 2026 IonQ also bought Vector Atomics, a company that makes atomic clocks. Jeremy Kahn, Fortune, 4 Feb. 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

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Cite this Entry

“Atomic clock.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic%20clock. Accessed 17 Apr. 2026.

Kids Definition

atomic clock

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

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