plutonium
noun
plu·to·ni·um
plü-ˈtō-nē-əm 
: 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
Examples of plutonium in a Sentence
Recent Examples on the Web
And despite decades of trying, the department has yet to fully clean up and dismantle the oozing, disintegrating tanks of highly radioactive wastes left over from plutonium processing at Hanford.
—
Michael Riordan, Scientific American, 31 Jan. 2025
Those images indicated heat signatures at the Yongbyon nuclear facility, suggesting the regime had resumed the reprocessing of plutonium and enriched uranium for an arsenal of bombs now estimated to number between 20 and 40.
—Victor Cha, Foreign Affairs, 22 Sep. 2021
Wheeler helped design nuclear reactors to produce plutonium, the key element that allows the bomb to work.
—Ken Bridges, Austin American-Statesman, 31 Dec. 2024
The lab is supposed to be building the capacity to produce thirty war-ready plutonium pits per year.
—Abe Streep, The New Yorker, 27 Dec. 2024
See all Example Sentences for plutonium 
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Michael Riordan, Scientific American, 31 Jan. 2025
Those images indicated heat signatures at the Yongbyon nuclear facility, suggesting the regime had resumed the reprocessing of plutonium and enriched uranium for an arsenal of bombs now estimated to number between 20 and 40.
—Victor Cha, Foreign Affairs, 22 Sep. 2021
Wheeler helped design nuclear reactors to produce plutonium, the key element that allows the bomb to work.
—Ken Bridges, Austin American-Statesman, 31 Dec. 2024
The lab is supposed to be building the capacity to produce thirty war-ready plutonium pits per year.
—Abe Streep, The New Yorker, 27 Dec. 2024
See all Example Sentences for plutonium
Dictionary Entries Near plutonium
Cite this Entry
“Plutonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plutonium. Accessed 5 Feb. 2025.
Copy CitationKids Definition
plutonium
noun
plu·to·ni·um
plü-ˈtō-nē-əm
: a radioactive metallic element that is formed by decay of neptunium and found in minute quantities in pitchblende and that produces atomic energy by fission see element
Medical Definition
plutonium
noun
plu·to·ni·um
plü-ˈtō-nē-əm
: 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
Love words? Need even more definitions?
Merriam-Webster unabridged
Share