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.

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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

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uranium Scientific  

/ y-rā′nē-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

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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.)

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Etymology

Origin of uranium

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

Compare meaning

How does uranium compare to similar and commonly confused words? Explore the most common comparisons:

• plutonium vs. uranium

Example Sentences

The material can be fairly quickly enriched to the 90% threshold needed for weapons-grade uranium.

From BBC

Meanwhile, he has referred to the war as “an excursion” and “a lovely stay,” yet he is also weighing a complex and risky mission to seize the regime’s uranium, the Journal reported.

From The Wall Street Journal

The highly enriched uranium is likely contained in 40 to 50 special cylinders that resemble scuba tanks.

From The Wall Street Journal

Securing Iran’s stores of enriched uranium could be feasible with special-operations forces and other troops, but it would be a highly complex mission.

From The Wall Street Journal

Asked if he intended to send U.S. troops into Iran to take its enriched uranium, he called it a “ridiculous question” that he wouldn’t answer.

From Los Angeles Times