deuterium

noun
deu·​te·​ri·​um | \ dü-ˈtir-ē-əm How to pronounce deuterium (audio) also dyü- \

Definition of deuterium

: an isotope of hydrogen that has one proton and one neutron in its nucleus and that has twice the mass of ordinary hydrogen symbol D

called also heavy hydrogen

Examples of deuterium in a Sentence

Recent Examples on the Web The isotopes butting heads will be deuterium and tritium. Laura Mallonee, Wired, "Fusion Energy Gets Ready to Shine—Finally," 21 Apr. 2020 Another experimental variation in 2016 involved replacing the electron with a muon in a deuterium atom—a heavier isotope of hydrogen, with a neutron as well as a proton and electron. Jennifer Ouellette, Ars Technica, "Physics not “broken” after all? We’re close to resolving proton radius puzzle," 5 Sep. 2019 The plasma is made of deuterium, a heavier isotope of hydrogen, and the goal is to bring it to temperatures and pressures at which colliding nuclei can fuse to form helium. Adrian Cho, Science | AAAS, "After decades of decline, the U.S. national fusion lab seeks a rebirth," 6 Feb. 2020 Protons and neutrons often collided, and some formed larger nuclei, such as that of deuterium (containing a proton and a neutron), as well as helium nuclei with two protons and two neutrons. Ryan C. Fortenberry, Scientific American, "The First Molecule in the Universe," 1 Feb. 2020 Replacing some of the deuterium with tritium, an even heavier isotope of hydrogen, could make the reactions self-sustaining. Adrian Cho, Science | AAAS, "After decades of decline, the U.S. national fusion lab seeks a rebirth," 6 Feb. 2020 The simplest fusion reaction to exploit involves two hydrogen isotopes, deuterium and tritium. Giulia Pacchioni, Scientific American, "The Road to Fusion," 26 Aug. 2019 In the past, researchers had measured palladium's deuterium content by tracking changes in its electrical resistance. Michael Greshko, National Geographic, "Cold fusion remains elusive—but these scientists may revive the quest," 29 May 2019 But as the researchers soon realized, packing palladium full of deuterium is extremely difficult, and so is measuring it. Michael Greshko, National Geographic, "Cold fusion remains elusive—but these scientists may revive the quest," 29 May 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'deuterium.' 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 deuterium

1933, in the meaning defined above

History and Etymology for deuterium

New Latin, from Greek deuteros second

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The first known use of deuterium was in 1933

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Cite this Entry

“Deuterium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/deuterium. Accessed 12 Jul. 2020.

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More Definitions for deuterium

deuterium

noun
deu·​te·​ri·​um | \ d(y)ü-ˈtir-ē-əm How to pronounce deuterium (audio) \

Medical Definition of deuterium

: an isotope of hydrogen that has one proton and one neutron in its nucleus and that has twice the mass of ordinary hydrogen

called also heavy hydrogen

More from Merriam-Webster on deuterium

Rhyming Dictionary: Words that rhyme with deuterium

Britannica.com: Encyclopedia article about deuterium

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