from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A naturally radioactive, silvery, metallic transuranic element, occurring in uranium ores and produced artificially by neutron bombardment of uranium. Its longest-lived isotope is Pu 244 with a half-life of 76 million years. It is a radiological poison, specifically absorbed by bone marrow, and is used, especially the highly fissionable isotope Pu 239, as a reactor fuel and in nuclear weapons. Atomic number 94; melting point 640°C; boiling point 3,235°C; specific gravity 19.84; valence 3, 4, 5, 6. See Table at element.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. The transuranic chemical element with atomic number 94 and symbol Pu.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a solid silvery grey radioactive transuranic element whose atoms can be split when bombarded with neutrons; found in minute quantities in uranium ores but is usually synthesized in nuclear reactors; 13 isotopes are known with the most important being plutonium 239


from The American Heritage® Dictionary of the English Language, 4th Edition

After the dwarf planet Pluto (from the fact that it follows neptunium in the periodic table).

from Wiktionary, Creative Commons Attribution/Share-Alike License

After Pluto (the entity formerly considered to be a planet).


  • “I'm sure that in 1985 plutonium is available in every corner drugstore, but in 1955 it's a little hard to come by.”

    Veronica Mars movie confirmed by Rob Thomas

  • In 2007, North Korea shut down its main plutonium-producing plant and agreed to end all nuclear programs in exchange for aid and diplomatic concessions.

    S. Korea Looks for Sincere Gesture from North

  • The half-life of (radioactive) plutonium is about 77,000 years.

    SciFi, Fantasy & Horror Collectibles - Part 6075

  • To reduce the risk of proliferation in the ME and help lay the basis for a regionwide nuclear weapon free zone, the US must ensure that plutonium is not separated from irradiated reactor fuel, insist on adequate international inspections of these countries, including the adoption of the Additional Protocol, and develop mechanisms to remove spent fuel from the region.

    16 « November « 2008 « Niqnaq

  • Given that just 8 kg of plutonium is enough to fabricate a nuclear weapon, this figure is significant.

    16 « November « 2008 « Niqnaq

  • Or we could convince congress to let NASA buy plutonium from the Russians, but their stocks are only a little larger than ours, and they aren't currently producing either.

    MSL Delay: Add 2 Years and $400 Million (and counting) - NASA Watch

  • And plutonium is difficult to handle — sufficiently radioactive to require shielding, awkward to transport without setting off radiation detectors, and extremely dangerous even in minute quantities if it is breathed in, swallowed, or absorbed through a cut or open wound.

    How to Get a Nuclear Bomb

  • Plutonium might work as the pollutant spread by a dirty bomb, but for your project, plutonium is out.

    How to Get a Nuclear Bomb

  • It requires chemical separation of plutonium from the other elements in spent fuel through a complex process that is much harder than using centrifuges to enrich uranium.

    Nuclear Power Play

  • The way you make plutonium is you run a reactor and after a few weeks or months you take the fuel rods out and put them in big vats of acid.

    How the Cold War Ended


Log in or sign up to get involved in the conversation. It's quick and easy.

  • Pu.

    December 16, 2007