uranium

noun

ura·​ni·​um yu̇-ˈrā-nē-əm 

often attributive

: a silvery heavy radioactive polyvalent metallic element that is found especially in uraninite and exists naturally as a mixture of mostly nonfissionable isotopes see Chemical Elements Table

Examples of uranium in a Sentence

Recent Examples on the Web

Over the course of the last year, Iran’s push to enrich uranium has only increased in pace and sophistication. —Carol E. B. Choksy, Foreign Affairs, 14 Oct. 2024

Iran’s nuclear program has progressed to a stage where, in approximately one week, the country could potentially enrich enough uranium for five fission weapons, according to estimates by Iran Watch, a website published by the Wisconsin Project on Nuclear Arms Control. —Lee Ying Shan, CNBC, 8 Oct. 2024

Plutonium is one of the two key ingredients used to manufacture nuclear weapons, along with highly enriched uranium. —Morgan Lee The Associated Press, arkansasonline.com, 5 Oct. 2024

The fiery rhetoric isn’t new, but comes at a time of tension on the Korean Peninsula and just weeks after North Korean state media released images of Kim visiting a uranium enrichment facility, which produces weapons-grade nuclear materials. —Yoonjung Seo, CNN, 4 Oct. 2024

Word History

Etymology

New Latin, from Uranus

First Known Use

1790, in the meaning defined above

Phrases Containing uranium

• uranium hexafluoride

Kids Definition

uranium

noun

ura·​ni·​um yȯ-ˈrā-nē-əm 

: a silvery heavy radioactive metallic element see element

Etymology

scientific Latin; named for the planet Uranus, from Latin Uranus, name of the god of heaven

Word Origin

The ancient Greek word ouranos meant "sky, heaven." It was fitting, then, for the Greeks to name their god of heaven Ouranos and their muse of astronomy Ourania. In Latin these names became Uranus and Urania. Uranus was the father of the god Saturn and the grandfather of Jupiter. In 1781 the English astronomer Sir William Herschel discovered by telescope the seventh planet of our solar system. It was the custom to name planets after Roman gods. Following this custom, the German astronomer Johann Bode suggested the name Uranus for this planet. It seemed a good idea since the fifth planet was called Jupiter and the sixth was Saturn. Eight years after the discovery of Uranus, the German chemist Martin Klaproth discovered a new element. He called it uranium after the new planet Uranus.

Medical Definition

uranium

noun

ura·​ni·​um yu̇-ˈrā-nē-əm 

: a silvery heavy radioactive polyvalent metallic element that is found especially in pitchblende and uraninite and exists naturally as a mixture of three isotopes of mass number 234, 235, and 238 in the proportions of 0.006 percent, 0.71 percent, and 99.28 percent respectively

—symbol U see Chemical Elements Table