plutonium

noun
plu·​to·​ni·​um | \ plü-ˈtō-nē-əm How to pronounce plutonium (audio) \

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

Examples of plutonium in a Sentence

Recent Examples on the Web Turkey has uranium deposits — the obligatory raw material — and over the decades has shown great interest in learning the formidable skills needed to purify uranium as well as to turn it into plutonium, the two main fuels of atom bombs. David E. Sanger, New York Times, "Erdogan’s Ambitions Go Beyond Syria. He Says He Wants Nuclear Weapons.," 20 Oct. 2019 Engineering Analytics will specifically be measuring for plutonium, americium and uranium and seeing whether levels of the radionuclides are a hazard to human health. John Aguilar, The Denver Post, "Trail plans prompt first soil samples in 13 years at Rocky Flats," 2 July 2019 The waste includes isotopes of iodine, strontium, americium, plutonium, uranium and other unstable elements, many of which are toxic as well as radioactive. Ralph Vartabedian, latimes.com, "Nuclear waste will be classified as safer under a controversial Trump administration change," 5 June 2019 Soon after residents cleared, a 51,000-person workforce—with employees from all across the country—descended on the area to extract plutonium from uranium for nuclear warfare. Tim Newcomb, Popular Mechanics, "The Long Fight to Clean Up America’s Cold War Nuclear Waste," 10 Dec. 2019 In 1974, Karen Silkwood, a 28-year-old technician and union activist at the Kerr-McGee Cimarron plutonium plant near Crescent, Okla., died in a car crash while on her way to meet a reporter. BostonGlobe.com, "In 1940, the Walt Disney film ‘‘Fantasia,’’ featuring animated segments set to classical music, had its world premiere in New York.," 13 Nov. 2019 If that was true, soil samples would not find plutonium. Dp Opinion, The Denver Post, "Letters: We should still be wary of Rocky Flats; Further examinations into U.S.-Iranian relations; Proposition CC: will it fix Colorado or ruin it? (10/27/19)," 28 Oct. 2019 Mission: Impossible — Fallout In the sixth installment of the action-movie franchise adapted from a classic TV spy series, IMF agent Ethan Hunt (Tom Cruise) leads his team to track down plutonium that vanished in a mission gone wrong. Los Angeles Times, "What’s on TV Saturday: “The Banana Splits Movie” on Syfy," 11 Oct. 2019 After joining an Oklahoma nuclear plant owned by Kerr-McGee, Silkwood discovered her body was contaminated with plutonium. Kevin Kelleher, Fortune, "How Whistleblowers Have Taken Down the Titans of American Business," 27 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'plutonium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of plutonium

1942, in the meaning defined above

History and Etymology for plutonium

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

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Time Traveler for plutonium

Time Traveler

The first known use of plutonium was in 1942

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Statistics for plutonium

Last Updated

7 Jan 2020

Cite this Entry

“Plutonium.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/plutonium. Accessed 29 January 2020.

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More Definitions for plutonium

plutonium

noun
How to pronounce plutonium (audio)

English Language Learners Definition of plutonium

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

plutonium

noun
plu·​to·​ni·​um | \ plü-ˈtō-nē-əm How to pronounce plutonium (audio) \

Kids Definition of plutonium

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

plutonium

noun
plu·​to·​ni·​um | \ plü-ˈtō-nē-əm How to pronounce plutonium (audio) \

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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More from Merriam-Webster on plutonium

Rhyming Dictionary: Words that rhyme with plutonium

Spanish Central: Translation of plutonium

Nglish: Translation of plutonium for Spanish Speakers

Britannica.com: Encyclopedia article about plutonium

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