atomic clock


Definition of 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)

Examples of atomic clock in a Sentence

Recent Examples on the Web This yields a 100-fold improvement over the cesium fountain clock, the gold standard for microwave atomic clocks. Andrew Ludlow, The Conversation, "Pairing lasers with microwaves makes mind-bogglingly accurate electronic clocks – a potential boon for GPS, cell phones and radar," 22 May 2020 Researchers must observe simultaneously with all the telescopes and synchronize the data recorded on computer disks at each site with the best atomic clocks. Mark J. Reid, Scientific American, "A New Map of the Milky Way," 17 Mar. 2020 That's why physicists have been developing all kinds of smaller experiments for detecting axions, from atomic clocks and resonating bars, to shining lasers at walls on the off-chance a bit of dark matter seeps through the other side. Jennifer Ouellette, Ars Technica, "Physicists propose listening for dark matter with plasma-based “axion radio”," 17 Oct. 2019 Instruments on satellites have measured the force of gravity all over the Earth to an accuracy of a few feet, which has been enough for atomic clocks in the past. Avery Thompson, Popular Mechanics, "Our New Atomic Clock Is So Precise That We Need a Better Understanding of Gravity To Use It," 30 Nov. 2018 At each of the eight observatories, the EHT team installed cameras and ultra-high-precision atomic clocks. Avery Thompson, Popular Mechanics, "Behind the Scenes of the First Black Hole Photo," 12 Apr. 2019 Science + Tech = MACH SpaceX launched its heftiest rocket yet with 24 research satellites, a deep space atomic clock, a solar sail and even the human ashes of a former astronaut. Petra Cahill, NBC News, "Iran slams sanctions, Jussie Smollett video released & stars perform Mueller report: The Morning Rundown," 25 June 2019 An atomic clock must be hyper-precise for travel through deep space, where everything is bigger and mistakes quickly can add up. Scottie Andrew, CNN, "NASA launched a Deep Space Atomic Clock that's like a GPS for space," 28 Aug. 2019 Cesium atomic clocks are precision devices that measure time using the frequency of atomic emissions from the element cesium, according to a website maintained by the U.S. Naval Observatory. Joe Dworetzky,, "South El Monte man charged with illegally exporting cesium atomic clocks," 28 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'atomic clock.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of atomic clock

1924, in the meaning defined above

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Time Traveler for atomic clock

Time Traveler

The first known use of atomic clock was in 1924

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Last Updated

28 May 2020

Cite this Entry

“Atomic clock.” Dictionary, Merriam-Webster, Accessed 5 Jun. 2020.

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More Definitions for atomic clock

atomic clock


English Language Learners Definition of atomic clock

: a special kind of clock that is extremely exact

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