uranium

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

Definition of uranium

  1. :  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

Origin and Etymology of uranium

New Latin, from Uranus


First Known Use: circa 1797


URANIUM Defined for English Language Learners

uranium

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

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

play
noun ura·ni·um \yu̇-ˈrā-nē-əm\

Definition of uranium for Students

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


Medical Dictionary

uranium

play
noun ura·ni·um \yu̇-ˈrā-nē-əm\

Medical Definition of uranium

  1. :  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



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