uranium 238


Definition of uranium 238

: an isotope of uranium of mass number 238 that is the most stable uranium isotope, that constitutes over 99 percent of natural uranium, that is not fissile but can be used to produce a fissile isotope of plutonium, and that has a half-life of 4.5 billion years

Examples of uranium 238 in a Sentence

Recent Examples on the Web The centrifuges are used to separate the rare, highly radioactive isotope, uranium 235, from the less radioactive type, uranium 238. BostonGlobe.com, "Most read on BostonGlobe.com," 5 Nov. 2019 The centrifuges are used to separate the rare, highly radioactive isotope, uranium 235, from uranium 238. David E. Sanger, New York Times, "Iran Adds Advanced Centrifuges, Further Weakening Nuclear Deal," 4 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'uranium 238.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of uranium 238

1942, in the meaning defined above

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The first known use of uranium 238 was in 1942

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Cite this Entry

“Uranium 238.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/uranium%20238. Accessed 23 Nov. 2020.

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