rubidium

noun

ru·​bid·​i·​um rü-ˈbi-dē-əm 

: 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

The group measured the ratios of light to heavy isotopes of both potassium and rubidium. —Jonathan O’Callaghan, Discover Magazine, 21 Oct. 2024

Their experiments involved shooting photons through a cloud of ultracold rubidium atoms and measuring the resulting degree of atomic excitation. —Manon Bischoff, Scientific American, 30 Sep. 2024

While studying the samples, the researchers were primarily looking for two elements both known to occur on the moon: potassium and rubidium. —Eric Lagatta, USA TODAY, 12 Aug. 2024

So the researchers measured the isotope ratios for both potassium and rubidium. —Will Sullivan, Smithsonian Magazine, 7 Aug. 2024

Word History

Etymology

New Latin, from Latin rubidus red, from rubēre

First Known Use

1861, in the meaning defined above

Kids Definition

rubidium

noun

ru·​bid·​i·​um rü-ˈbid-ē-əm 

: a soft silvery metallic element that reacts violently with water see element

Medical Definition

rubidium

noun

ru·​bid·​i·​um rü-ˈbid-ē-əm 

: a soft silvery metallic element that decomposes water with violence and bursts into flame spontaneously in air

—symbol Rb see Chemical Elements Table