plutonium

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noun plu·to·ni·um \plü-ˈtō-nē-əm\

Definition of plutonium

  1. :  a radioactive metallic element similar chemically to uranium that is formed as the isotope 239 by decay of neptunium and found in minute quantities in pitchblende, that undergoes slow disintegration with the emission of an alpha particle to form uranium 235, and that is fissionable with slow neutrons to yield atomic energy — see element table

Origin and Etymology of plutonium

New Latin, from Pluton-, Pluto, the planet Pluto


First Known Use: 1942


PLUTONIUM Defined for English Language Learners

plutonium

play
noun plu·to·ni·um \plü-ˈtō-nē-əm\

Definition of plutonium for English Language Learners

  • : a radioactive element that is used to make nuclear energy and nuclear weapons


PLUTONIUM Defined for Kids

plutonium

play
noun plu·to·ni·um \plü-ˈtō-nē-əm\

Definition of plutonium for Students

  1. :  a radioactive metallic chemical element formed from neptunium and used for releasing atomic energy


Medical Dictionary

plutonium

play
noun plu·to·ni·um \plü-ˈtō-nē-əm\

Medical Definition of plutonium

  1. :  a radioactive metallic element similar chemically to uranium that is formed as the isotope 239 by decay of neptunium and found in minute quantities in pitchblende, that undergoes slow disintegration with the emission of an alpha particle to form uranium 235, and that is fissionable with slow neutrons to yield atomic energy—symbol Pu; see element table



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