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Noun: plutonium  ploo'tow-nee-um
  1. 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
    "weapons-grade plutonium";
    - Pu, atomic number 94

Derived forms: plutoniums

Type of: chemical element, element

Encyclopedia: Plutonium