: a metallic chemical element that is the most electropositive element known and that is used in photoelectric cells, in atomic clocks, and as a component of drilling fluid see Chemical Elements Table
Examples of cesium in a Sentence
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Germanium semiconductor detectors, radioactive cesium concentration detectors, sodium iodide scintillation spectrometers and more scan the produce for any signs of radioactivity.
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Kate Graham-Shaw, Scientific American, 9 Oct. 2024
An array of radioactive substances had been released during the disaster, including plutonium and uranium, but scientists were also on the lookout for harmful levels of radioactive cesium and iodine isotopes, which turned out to be the abundant and far-reaching contaminants of agricultural land.
—Kate Graham-Shaw, Scientific American, 9 Oct. 2024
The current gold standard for ultra-precise timekeeping is the cesium atomic clock, where the tiny and fixed energy transitions of the atom’s electrons are used to keep track of time.
—Shi En Kim, Smithsonian Magazine, 23 Sep. 2024
Scientists use a laser to bathe a cesium atom with photons.
—Quanta Magazine, 4 Sep. 2024
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Kate Graham-Shaw, Scientific American, 9 Oct. 2024
An array of radioactive substances had been released during the disaster, including plutonium and uranium, but scientists were also on the lookout for harmful levels of radioactive cesium and iodine isotopes, which turned out to be the abundant and far-reaching contaminants of agricultural land.
—Kate Graham-Shaw, Scientific American, 9 Oct. 2024
The current gold standard for ultra-precise timekeeping is the cesium atomic clock, where the tiny and fixed energy transitions of the atom’s electrons are used to keep track of time.
—Shi En Kim, Smithsonian Magazine, 23 Sep. 2024
Scientists use a laser to bathe a cesium atom with photons.
—Quanta Magazine, 4 Sep. 2024
See all Example Sentences for cesium
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Cite this Entry
“Cesium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cesium. Accessed 2 Dec. 2024.
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Medical Definition
cesium
noun
ce·si·um
variants
or chiefly British caesium
: 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
—symbol Cs
see Chemical Elements Table
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