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 Urey, of course, was a Nobel Prize-winning scientist who discovered the isotopes of hydrogen, like deuterium, and so on. Quanta Magazine, 1 June 2022 The Nuclear Regulatory Commission will also halt general licenses for exports of source material, special material, byproduct material and deuterium to Russia. Courtney Subramanianstaff Writer, Los Angeles Times, 8 May 2022 The 50 million watts is only the power supplied directly to the deuterium and tritium fuel. Don Lincoln, CNN, 11 Feb. 2022 Set up to reflect the design of ITER, and with the mix of deuterium and tritium fuel that will be used there, JET made the largest sustained fusion reaction yet. John Timmer, Ars Technica, 9 Feb. 2022 Unfortunately, the heated deuterium makes its own magnetic fields, which interfere with the force fields. Don Lincoln, CNN, 11 Feb. 2022 According to Daly, the Sun has very low levels of heavy hydrogen called deuterium. Joshua Hawkins, BGR, 7 Dec. 2021 In theory, deuterium can be obtained from Earth's oceans; one liter of seawater is estimated to have enough fusion material to produce energy equivalent to 300 liters of gasoline, Newsweek reports. Elizabeth Gamillo, Smithsonian Magazine, 10 Jan. 2022 The extra performance of the new OLED EX displays isn’t solely down to the influence of deuterium, however. John Archer, Forbes, 29 Dec. 2021 See More

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.

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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Time Traveler for deuterium

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The first known use of deuterium was in 1933

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Dictionary Entries Near deuterium



deuterium oxide

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Last Updated

23 Jun 2022

Cite this Entry

“Deuterium.” Dictionary, Merriam-Webster, Accessed 20 Aug. 2022.

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More Definitions for deuterium


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 Encyclopedia article about deuterium


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