mass number


Definition of mass number

: an integer that approximates the mass of an isotope and designates the number of nucleons in the nucleus

Examples of mass number in a Sentence

Recent Examples on the Web Somehow, the mass number of people upgrading to Big Sur on Thursday seems to have caused the servers at to become overloaded but not fall over completely. Dan Goodin, Ars Technica, "Mac certificate check stokes fears that Apple logs every app you run," 16 Nov. 2020 But the city's unrest continues to stem from the horrifying footage of Blake's shooting and the mass number of unarmed Black men who have been the target of police violence., "A Group Of Armed Men Shot & Killed Two Jacob Blake Protestors In Kenosha," 26 Aug. 2020 Venues that can house mass numbers of patients, such as a sports stadium in Nigeria, are being identified, Stephen said. NBC News, "African countries that faced Ebola outbreaks use lessons to fight COVID-19, experts say," 9 Apr. 2020 Luckily, these Zoom calls have been spared from the mass number of spammers attacking such video classes with racist and anti-Semitic writings. Elle Weber, cleveland, "A high school senior’s perspective on life during the coronavirus crisis," 4 Apr. 2020 Some venues have already decided to close altogether because of the mass number of cancellations and postponements. Stephanie Cain, Fortune, "Venues are getting a crash course in postponement clauses thanks to coronavirus," 19 Mar. 2020 Here are tips to get refunds The Wisconsin Department of Agriculture, Trade and Consumer Protection is reminding consumers of their right to a refund given the mass number of cancellations because of COVID-19. Milwaukee Journal Sentinel, "Live coronavirus updates: 40 cases confirmed in Milwaukee County, including 13 in city, 27 in suburbs," 17 Mar. 2020 The network infrastructure just can't cope with mass numbers of devices, leading to slower data speeds and longer lag time for downloads. Clare Duffy, CNN, "The big differences between 4G and 5G," 17 Jan. 2020 With mass numbers of sea stars dead, the urchins proliferated, chomping their way through the kelp forests. Brigit Katz, Smithsonian, "Voracious Purple Sea Urchins Are Ravaging Kelp Forests on the West Coast," 26 Oct. 2019

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

1923, in the meaning defined above

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Time Traveler for mass number

Time Traveler

The first known use of mass number was in 1923

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Cite this Entry

“Mass number.” Dictionary, Merriam-Webster, Accessed 4 Mar. 2021.

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More Definitions for mass number

mass number


Medical Definition of mass number

: an integer that approximates the mass of an isotope and that designates the number of nucleons in the nucleus the symbol for carbon of mass number 14 is 14C or C14 — compare atomic mass

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