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atomic clock

an extremely accurate electronic clock regulated by the resonance frequency of atoms or molecules of certain substances, as cesium.
Origin of atomic clock
1935-40 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for atomic clock
  • The atomic clock may have slowed a bit, but it is still ticking.
  • He was a self-educated mathematician and amateur scientist who bought an atomic clock and an electron microscope.
  • It would go everywhere you go, and it would always be correct since it would be an atomic clock.
  • His work would end up making the atomic clock even more precise.
  • Scientists have manufactured the world's smallest atomic clock, with inner machinery about the size of a grain of rice.
  • The plot ticks along with the iron reliability of an atomic clock.
  • Research aimed at developing an atomic clock focused first on microwave resonances in the ammonia molecule.
  • However, by taking a measurement from a fourth satellite, the receiver avoids the need for an atomic clock.
  • The world's atomic clock timekeepers got all excited.
British Dictionary definitions for atomic clock

atomic clock

an extremely accurate clock in which an electrical oscillator is controlled by the natural vibrations of an atomic or molecular system such as caesium or ammonia
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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atomic clock in Science
atomic clock  
An extremely precise clock whose rate is controlled by a periodic process (such as vibration, or the absorption or emission of electromagnetic radiation) that occurs at a steady rate in atoms or molecules. The standard atomic clock is based on the vibrations of cesium atoms and is so accurate that it would gain or lose less than one second in three million years. Atomic clocks are used to help track satellites, run navigation systems, and study movements of the Earth's crust.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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atomic clock in Culture

atomic clock definition

The most accurate clock available. Time is measured by the movement of electrons in cesium atoms. The standard second is now defined by measurements on an atomic clock.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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