plutonium

[ ploo-toh-nee-uhm ]

noun

, Chemistry, Physics.

1. a transuranic element with a fissile isotope of mass number 239 plutonium 239 that can be produced from non-fissile uranium 238, as in a breeder reactor. : Pu; : 94.

plutonium

/ pluːˈtəʊnɪəm /

noun

1. a highly toxic metallic transuranic element. It occurs in trace amounts in uranium ores and is produced in a nuclear reactor by neutron bombardment of uranium-238. The most stable and important isotope, plutonium-239 , readily undergoes fission and is used as a reactor fuel in nuclear power stations and in nuclear weapons. Symbol: Pu; atomic no: 94; half-life of ²³⁹Pu: 24 360 years; valency: 3, 4, 5, or 6; relative density (alpha modification): 19.84; melting pt: 640°C; boiling pt: 3230°C

plutonium

/ plo̅o̅-tō′nē-əm /

1. A silvery, radioactive metallic element of the actinide series that has the highest atomic number of all naturally occurring elements. It is found in minute amounts in uranium ores and is produced artificially by bombarding uranium with neutrons. It is absorbed by bone marrow and is highly poisonous. Plutonium is used in nuclear weapons and as a fuel in nuclear reactors. Its longest-lived isotope is Pu 244 with a half-life of 80 million years. Atomic number 94; melting point 640°C; boiling point 3,228°C; specific gravity 19.84; valence 3, 4, 5, 6.
2. See Periodic Table

plutonium

1. A radioactive chemical element that is artificially derived from uranium .

Notes

Plutonium is used in nuclear reactors .

Word History and Origins

Origin of plutonium¹

1940–45; < Greek Ploútōn Pluto + -ium

Word History and Origins

Origin of plutonium¹

C20: named after the dwarf planet Pluto because Pluto lies beyond Neptune and plutonium was discovered soon after neptunium

Example Sentences

Researchers there were helping design nuclear reactors to produce the plutonium needed to create an atomic bomb.

From Science News

Within one piece of the sample, the scientists searched for a variety of plutonium called plutonium-244, which is produced by the r-process.

From Science News

The scientists can’t say if the plutonium they detected also came from those supernovas.

From Science News

Scientists had long suspected that elements such as gold, silver and plutonium are born during supernovas, when stars explode.

From Science News

Researchers compared the plutonium count to atoms that had a known source.

From Science News

When my oldest child was a toddler, I treated illuminated screens like plutonium.

From The Daily Beast

The reactor has the potential to produce weapons grade plutonium.

From The Daily Beast

The reactor has the potential to produce weapon grade plutonium.

From The Daily Beast

No one seems worried about 30 to 40 pounds of missing plutonium.

From The Daily Beast

But on his watch North Korea, the chief target of his ire, reprocessed enough plutonium to make six new nuclear weapons.

From The Daily Beast

I wonder if he mightn't have some idea of what else plutonium can be used for, beside generating power.

From Project Gutenberg

He also managed to convey King Orgzild's pleasure at having obtained the plutonium.

From Project Gutenberg

You see, the uranium or plutonium fission-bomb's been obsolete for over four hundred years.

From Project Gutenberg

Here was also a sacred cavern, styled by Strabo Plutonium, and Charonium; which sent up pestilential effluvia.

From Project Gutenberg

Rip went to it and examined the raw plutonium, being careful to keep the pieces widely separated.

From Project Gutenberg