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uranium

American  
[yoo-rey-nee-uhm] / yʊˈreɪ ni əm /

noun

Chemistry.
  1. a white, lustrous, radioactive, metallic element, occurring in pitchblende, and having compounds that are used in photography and in coloring glass. The 235 isotope is used in atomic and hydrogen bombs and as a fuel in nuclear reactors. U; 238.03; 92; 19.07.


uranium British  
/ jʊˈreɪnɪəm /

noun

  1. a radioactive silvery-white metallic element of the actinide series. It occurs in several minerals including pitchblende, carnotite, and autunite and is used chiefly as a source of nuclear energy by fission of the radioisotope uranium-235 . Symbol: U; atomic no: 92; atomic wt: 238.0289; half-life of most stable isotope, 238 U: 451 × 10 9 years; valency: 2-6; relative density: 18.95 (approx.); melting pt: 1135°C; boiling pt: 4134°C

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

uranium Scientific  
/ y-rānē-əm /
  1. A heavy, silvery-white, highly toxic, radioactive metallic element of the actinide series. It has 14 known isotopes, of which U 238 is the most naturally abundant, occurring in several minerals. Fissionable isotopes, especially U 235, are used in nuclear reactors and nuclear weapons. Atomic number 92; atomic weight 238.03; melting point 1,132°C; boiling point 3,818°C; specific gravity 18.95; valence 2, 3, 4, 5, 6.

  2. See Periodic Table


uranium Cultural  
  1. A chemical element that is naturally radioactive. An isotope of uranium, uranium 235, is the main fuel for nuclear reactors and atomic bombs (see also atomic bomb). Its symbol is U. (See fission and chain reaction.)


Etymology

Origin of uranium

From New Latin, dating back to 1790–1800; Uranus, -ium

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“They are very complex ores with highly unusual mineralogy, and some of them have relatively high contents of the radioactive elements uranium and thorium,” Goodenough notes.

From Barron's

“They are very complex ores with highly unusual mineralogy, and some of them have relatively high contents of the radioactive elements uranium and thorium,” Goodenough notes.

From Barron's

Apart from geopolitics, he sees oil destined to cycle like other commodities such as uranium, gold, recently silver and probably copper is next.

From MarketWatch

Energy Department on Monday said it awarded $2.7 billion to nuclear fuel makers to boost the domestic supply of enriched uranium.

From The Wall Street Journal

But in recent years, there has been increased interest in Greenland's natural resources, including mining for rare earth minerals, uranium and iron.

From BBC