caesium clock

British  

noun

1. a type of atomic clock that uses the frequency of radiation absorbed in changing the spin of electrons in caesium atoms See also second 2

---

Example Sentences

Once it is there, the pips’ journey time through the fibre-optic cable can be worked out, by logging the discrepancy between what the pips say and what the caesium clock says.

From Economist

Even if the clocks pass this later test, usurping the caesium clock to create a more precise definition of the second will not be easy.

From Nature

It's because this transition frequency is so much higher than the resonant frequency of quartz that a caesium clock is so much more accurate.

From BBC

And if the fibre connection bringing the pips should be cut, the caesium clock takes over until a connection is restored.

From Economist

It was here in the 1930s that the physicist Louis Essen developed the first quartz ring clock, the most accurate timepiece of its day, and a precursor of the caesium clock.

From BBC