ru·​bid·​i·​um | \ rü-ˈbi-dē-əm How to pronounce rubidium (audio) \

Definition of rubidium

: a soft silvery metallic element of the alkali metal group that reacts violently with water and bursts into flame spontaneously in air — see Chemical Elements Table

Examples of rubidium in a Sentence

Recent Examples on the Web

To do this, Stenhauer shot a laser composed of rubidium atoms through an environment cooled to almost absolute zero. Sophie Weiner, Popular Mechanics, "Physicist Creates Lab-Sized "Black Hole"," 26 Aug. 2016 The equipment will cool rubidium and potassium atoms by scattering laser light off the particles in all directions to slow them to almost a standstill. Elizabeth Gibney, Scientific American, "Universe’s Coolest Lab Set to Open Quantum World," 9 May 2018 This keeps the rubidium atoms diffuse, slow moving and in a highly excited state. Marissa Fessenden, Smithsonian, "Scientists Create a New Form of Light by Linking Photons," 16 Feb. 2018 But vaporizing rubidium with a laser and keeping it ultracold creates a cloud the researchers contain in a small tube and magnetize. Marissa Fessenden, Smithsonian, "Scientists Create a New Form of Light by Linking Photons," 16 Feb. 2018 Cornell and Wieman were trying to cool a puff of rubidium gas to within a few billionths of a degree of absolute zero—colder than any place in nature, even the 2.73 kelvins of space. Adrian Cho, Science | AAAS, "Coolest science ever headed to the space station," 7 Sep. 2017 In the case of the Judeo-Christian Bible, there's nothing about rubidium and strontium, the five layers of the atmosphere, anything like that. Jack Holmes, Esquire, "Bill Nye Doesn't Have an Opinion. He Has Science.," 26 Oct. 2017 The Cold Atom Clock Experiment in Space (CACES) involves trapping, cooling, and probing rubidium atoms within a box that could fit in the trunk of a car. Edwin Cartlidge, Science | AAAS, "China’s atomic clock passes space test," 20 Sep. 2017 The new model suggests our home planet contains significantly more sodium, potassium, chlorine, zinc, strontium, fluorine, gallium, rubidium, niobium, gadolinium, tantalum, helium, argon, and krypton than previously believed. Jay Bennett, Popular Mechanics, "Scientists Create Most Accurate Estimate of Earth's Composition," 18 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'rubidium.' 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 rubidium

1861, in the meaning defined above

History and Etymology for rubidium

New Latin, from Latin rubidus red, from rubēre

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The first known use of rubidium was in 1861

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ru·​bid·​i·​um | \ rü-ˈbid-ē-əm How to pronounce rubidium (audio) \

Medical Definition of rubidium

: a soft silvery metallic element that decomposes water with violence and bursts into flame spontaneously in air symbol Rb — see Chemical Elements Table

More from Merriam-Webster on rubidium

Rhyming Dictionary: Words that rhyme with rubidium Encyclopedia article about rubidium

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