radioactivity

noun
ra·​dio·​ac·​tiv·​i·​ty | \ ˌrā-dē-ō-ak-ˈti-və-tē How to pronounce radioactivity (audio) \

Definition of radioactivity

: the property possessed by some elements (such as uranium) or isotopes (such as carbon 14) of spontaneously emitting energetic particles (such as electrons or alpha particles) by the disintegration of their atomic nuclei also : the rays emitted

Examples of radioactivity in a Sentence

Recent Examples on the Web The resulting waste contains a more concentrated radioactivity and produces radon gas, a hazardous air pollutant, according to an EPA press release from earlier this month. Tyler Van Dyke, Washington Examiner, "EPA approves use of radioactive fertilizer byproduct in roads," 27 Oct. 2020 Russia has denied being the source of the radioactivity, but the country had similar leaks in 2017 and 2019. Kyle Mizokami, Popular Mechanics, "Radiation Leak in Europe Points to a Possible Russian Weapons Test," 29 June 2020 But its fuel, usually isotopes of hydrogen, would be far more plentiful than the uranium used in most nuclear plants, and fusion would generate less, and less dangerous, radioactivity and waste than fission plants. Daniel Tenreiro, National Review, "The Capital Note: Surge in Entrepreneurship amid Pandemic," 30 Sep. 2020 The notorious case ultimately led to a lasting impact in the area of workplace health and safety, as well as the study of radioactivity. Ruth Kinane, EW.com, "Joey King fights for female factory workers in Radium Girls clip," 22 Sep. 2020 And engineers will need to figure out how to harness the wastes while preventing the release of heavy metals and radioactivity locked in the material. Robert F. Service, Science | AAAS, "Industrial waste can turn planet-warming carbon dioxide into stone," 3 Sep. 2020 Why did America suppress the truth about the radioactivity generated by the bombs that doomed countless survivors to death later? Edward Kosner, WSJ, "‘Fallout’ Review: Hiroshima and After," 30 Aug. 2020 It has been estimated that the July 1959 incident expelled 240 times the amount of radioactivity as Three Mile Island. Yxta Maya Murray, Longreads, "Fire/Flood: A Southern California Pastoral," 19 Aug. 2020 Radiation monitoring stations across northern Europe have detected above normal—but still safe—levels of radioactivity. Kyle Mizokami, Popular Mechanics, "Radiation Leak in Europe Points to a Possible Russian Weapons Test," 29 June 2020

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

1899, in the meaning defined above

History and Etymology for radioactivity

International Scientific Vocabulary

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Time Traveler for radioactivity

Time Traveler

The first known use of radioactivity was in 1899

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Statistics for radioactivity

Last Updated

4 Nov 2020

Cite this Entry

“Radioactivity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radioactivity. Accessed 30 Nov. 2020.

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More Definitions for radioactivity

radioactivity

noun
ra·​dio·​ac·​tiv·​i·​ty | \ ˌrā-dē-ō-ak-ˈti-və-tē How to pronounce radioactivity (audio) \

Kids Definition of radioactivity

1 : the giving off of rays of energy or particles by the breaking apart of atoms of certain elements (as uranium)
2 : the rays or particles that are given off when atoms break apart

radioactivity

noun
ra·​dio·​ac·​tiv·​i·​ty | \ -ak-ˈtiv-ət-ē How to pronounce radioactivity (audio) \
plural radioactivities

Medical Definition of radioactivity

: the property possessed by some elements (as uranium) or isotopes (as carbon 14) of spontaneously emitting energetic particles (as electrons or alpha particles) by the disintegration of their atomic nuclei

More from Merriam-Webster on radioactivity

Nglish: Translation of radioactivity for Spanish Speakers

Britannica.com: Encyclopedia article about radioactivity

Comments on radioactivity

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