uranium

[ yoo-rey-nee-uhm ]

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

/ 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, ²³⁸U: 451 × 10 ⁹years; valency: 2-6; relative density: 18.95 (approx.); melting pt: 1135°C; boiling pt: 4134°C

uranium

/ 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

uranium

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 .)

Word History and Origins

Origin of uranium¹

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

Word History and Origins

Origin of uranium¹

C18: from New Latin, from Uranus ²; from the fact that the element was discovered soon after the planet

Example Sentences

Also, large amounts of uranium would have required the presence of lots of neutrons.

From Singularity Hub 

Violent explosions of massive, magnetized stars may forge most of the universe’s heavy elements, such as silver and uranium.

From Science News

After blasting uranium with neutrons, Fermi and colleagues reported evidence of success.

From Science News

Among the provocative moves, Iran began enriching uranium at levels beyond caps outlined in the accord.

From Vox

The researchers’ uranium snowflake proposal is an entirely new mechanism that might explain a small fraction of type 1a supernovas, without the need for another star.

From Science News

Importantly, as part of the interim plan, Iran has diluted or converted its stockpile of 20 percent enriched uranium.

From The Daily Beast

And that conglomerate also owns nearly 70 percent of the Rossing uranium mine in Namibia.

From The Daily Beast

Since then, all dividend payments have been frozen and Iran receives “no uranium or revenue from the mine.”

From The Daily Beast

A drawing of what was deemed a “deer pig” was also sent through the uranium decay ringer.

From The Daily Beast

He referred to this risky state of affairs as “the babushka-with-uranium-in-the-chicken-shed” problem.

From The Daily Beast

It's not controllable enough and uranium isn't something we could carry by the ton.

From Project Gutenberg

But the osmium and uranium alloyed with it are something else.

From Project Gutenberg

Radium was discovered in 1898 by M. and Madame Curie and M. Bmont, while experimenting with the uranium mineral pitchblende.

From Project Gutenberg

From the steel-like ground they scooped a dozen tons of the dirty black uranium ore and sent it hurtling back to the Bertha.

From Project Gutenberg

They flew about a huge stack of lead containers—uranium cells secured for the long trip home.

From Project Gutenberg