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
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There's no commercial purpose for enriching uranium at 60 percent.
—
CBS News, 16 Mar. 2025
Iran now enriches uranium to near weapons-grade levels of 60%, the only country in the world without a nuclear weapons program to do so.
—Jon Gambrell, Los Angeles Times, 14 Mar. 2025
Near Weapons-Grade Uranium On Wednesday, the U.N. Security Council held a closed-door meeting to discuss Iran's increase in its stockpile of uranium near weapons-grade levels.
—Raja Krishnamoorthi, Newsweek, 13 Mar. 2025
In the south, it's believed that there are valuable deposits of oil and gas, as well as untapped rare earth minerals like uranium and zinc, which are used for consumer electronics products, clean energy and defense technologies.
—Kim Hjelmgaard, USA TODAY, 11 Mar. 2025
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CBS News, 16 Mar. 2025
Iran now enriches uranium to near weapons-grade levels of 60%, the only country in the world without a nuclear weapons program to do so.
—Jon Gambrell, Los Angeles Times, 14 Mar. 2025
Near Weapons-Grade Uranium On Wednesday, the U.N. Security Council held a closed-door meeting to discuss Iran's increase in its stockpile of uranium near weapons-grade levels.
—Raja Krishnamoorthi, Newsweek, 13 Mar. 2025
In the south, it's believed that there are valuable deposits of oil and gas, as well as untapped rare earth minerals like uranium and zinc, which are used for consumer electronics products, clean energy and defense technologies.
—Kim Hjelmgaard, USA TODAY, 11 Mar. 2025
See All Example Sentences for uranium
Cite this Entry
“Uranium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/uranium. Accessed 23 Mar. 2025.
Copy CitationKids 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
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