Definition of cesium
: a silver-white soft ductile element of the alkali metal group that is the most electropositive element known and that is used especially in photoelectric cells — see element table
Recent Examples of cesium from the Web
Around the same time, the first accurate atomic clocks were being developed that used cesium.
The city of Soma last year set up municipal incinerators specially designed to burn carcasses and filter out radioactive cesium.
Leap seconds are used to fill in the gap and make Earth’s observed speed align with our most accurate clocks—atomic devices that define a second by measuring the regular decay of radioactive elements such as cesium.
Stuhlinger wrote that cesium would make a more efficient propellant than rubidium.
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Origin and Etymology of cesium
New Latin, from Latin caesius bluish gray
First Known Use: 1861See Words from the same year
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