plutonium

noun plu·to·ni·um \ plü-ˈtō-nē-əm \
Updated on: 14 Nov 2017

Definition of plutonium

: 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 Chemical Elements Table

Recent Examples of plutonium from the Web

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Origin and Etymology of plutonium

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


PLUTONIUM Defined for English Language Learners

plutonium

noun

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

noun plu·to·ni·um \ plü-ˈtō-nē-əm \

Definition of plutonium for Students

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

Medical Dictionary

plutonium

noun plu·to·ni·um \ plü-ˈtō-nē-əm \

medical Definition of plutonium

: 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 Chemical Elements Table


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