a radioactive, metallic chemical element, one of the actinides, found in trace quantities in native uranium ores and produced by bombarding uranium with deuterons: symbol, Pu; at. no. 94: its most important isotope (plutonium-239) is used in nuclear weapons and as a reactor fuel
Origin of plutoniumModL, after the planet Pluto + -ium: so named (1942) by G. T. Seaborg, one of the United States physicists who isolated it, because its atomic number is next after that of neptunium, as Pluto's orbit is next after Neptune's
A 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 80 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 3,228°C; specific gravity 19.84 (25°C); valence 3, 4, 5, 6. See Periodic Table.
Origin of plutoniumAfter the dwarf planet Pluto (from the fact that it follows neptunium in the periodic table).
- The transuranic chemical element with atomic number 94 and symbol Pu.
After Pluto (the entity formerly considered to be a planet).