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uranium

u·ra·ni·um [ y ráynee əm ]


noun 
Definition:
 
radioactive chemical element: a heavy silvery white radioactive metallic element occurring in three isotopes. Source: uraninite, pitchblende. Use: in one isotope, as fuel in nuclear reactors and weapons.
Symbol  U


[Late 18th century. < modern Latin< Uranus the planet (discovered eight years before the element was identified)]
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