Definition of uranium
: a silvery heavy radioactive polyvalent metallic element that is found especially in uraninite and exists naturally as a mixture of mostly nonfissionable isotopes — see element table
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Recent Examples of uranium from the Web
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Precious coolant — dropped, exposing the uranium rods at least two feet below the top.
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McNeice was a rich kid who'd inherited millions from his family's uranium mining fortune.
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Other harmful colors include fluorescent radium green, arsenic green, and uranium orange.
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In order to date these minerals, the group used the steady decay of radioactive uranium to lead.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'uranium'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of uranium
New Latin, from Uranus
First Known Use: circa 1797
URANIUM Defined for English Language Learners
uranium
playDefinition of uranium for English Language Learners
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: a radioactive element that is used to make nuclear energy and nuclear weapons
URANIUM Defined for Kids
uranium
playDefinition of uranium for Students
: a radioactive metallic chemical element used as a source of atomic energy
Medical Dictionary
uranium
playMedical Definition of uranium
: 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 element table
Learn More about uranium
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See words that rhyme with uranium Spanish Central: Translation of uranium Nglish: Translation of uranium for Spanish speakers Britannica English: Translation of uranium for Arabic speakers Britannica.com: Encyclopedia article about uranium
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