uranium

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

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

Full 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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Origin of URANIUM

New Latin, from Uranus

First Known Use: circa 1797

Rhymes with URANIUM

geranium, germanium, titanium

URANIUM Defined for Kids

uranium

noun ura·ni·um \yu̇-ˈrā-nē-əm\

Definition of URANIUM for Kids

: 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 element table