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

At the heart of their system is a proprietary quantum magnetometer, which measures the way an external field influences the spin of rubidium atoms, in a compact, lightweight package about the size of a Rubik’s cube. —The Physics Arxiv Blog, Discover Magazine, 22 Apr. 2025

The unique, patentable aspect of the project, Simon says, might be the use of a weakly acidic solution that pulls out only rubidium, or rubidium plus lithium. —IEEE Spectrum, 11 Feb. 2025

China remains a key supplier of minerals to the U.S., ranking second only to Canada in overall net import reliance, and is the principal import source for many of the 50 minerals America considers critical, such as graphite, tantalum and rubidium. —John Feng, Newsweek, 2 Mar. 2025

Then, dilute acid is poured through the column in order to pull the rubidium off the resin, flushing a solution of only rubidium out the other side of the column. —IEEE Spectrum, 11 Feb. 2025

Word History

Etymology

New Latin, from Latin rubidus red, from rubēre

First Known Use

1861, in the meaning defined above

Rhymes for rubidium

• clostridium
• cranidium
• cymbidium
• iridium
• peridium
• presidium
• pygidium
• cryptosporidium
• idiom

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