uranium

noun, often attributive ura·ni·um \ yu̇-ˈrā-nē-əm \

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 Chemical Elements Table

Recent Examples of uranium from the Web

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Origin and Etymology of uranium

New Latin, from Uranus


URANIUM Defined for English Language Learners

uranium

noun

Definition of uranium for English Language Learners

  • : a radioactive element that is used to make nuclear energy and nuclear weapons


URANIUM Defined for Kids

uranium

noun ura·ni·um \ yu̇-ˈrā-nē-əm \

Definition of uranium for Students

:a radioactive metallic chemical element used as a source of atomic energy

Medical Dictionary

uranium

noun ura·ni·um \ yu̇-ˈrā-nē-əm \

medical 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 Chemical Elements Table


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