uranium

n. silvery white radioactive metallic element whose atomic number is 92 used in nuclear reactions and atomic bombs

Uranium is a white/black metallic chemical element in the actinide series of the periodic table that has the symbol U and atomic number 92. It has 92 protons and electrons, 6 of them valence electrons. It can have between 141 and 146 neutrons, with 143 and 146 in its most common isotopes. Uranium has the highest atomic weight of the naturally occurring elements (see plutonium). Uranium is approximately 70% more dense than lead and is weakly radioactive. It occurs naturally in low concentrations (a few parts per million) in soil, rock and water, and is commercially extracted from uranium-bearing minerals such as uraninite (see uranium mining).
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Noun
1. a heavy toxic silvery-white radioactive metallic element; occurs in many isotopes; used for nuclear fuels and nuclear weapons
(synonym) U, atomic number 92
(hypernym) metallic element, metal
(hyponym) uranium 235
(substance-holonym) uraninite, pitchblende

n. uranium, radioactive metallic element used in nuclear reactions and atomic bombs

n. uranium, silvery white radioactive metallic element used in nuclear reactions and atomic bombs