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 site is designed to last at least 300 years after the last shipment arrives, when the radioactivity of its contents is forecast to be no higher than levels found in nature. NBC News, 4 Nov. 2021 Testing of sea creatures in the surrounding lagoon, including giant clams, shows high levels of radioactivity. Susanne Rust Staff Writer, Los Angeles Times, 22 Oct. 2021 Featuring high temperatures, toxic chemicals, and radioactivity, the toys are now deemed too dangerous for their precocious prepubescent audience. Jonathon Keats, Forbes, 12 Oct. 2021 In 1986, one of Chernobyl’s reactors melted down, causing massive explosions that crippled the plant and sent waves of radioactivity billowing across Europe. oregonlive, 20 May 2021 The site has only trace amounts of radioactivity, Mr. Barnes said from Australia, but rich deposits of metals like tantalum, used in mobile phones, and zirconium, used in fuel cells and various kinds of electronics. New York Times, 1 Oct. 2021 Interim Storage Partners plan to build the facility next to an existing dump site in Andrews County, near the Texas-New Mexico state line, for low-level waste such as protective clothing and other material that has been exposed to radioactivity. From Usa Today Network And Wire Reports, USA TODAY, 16 Sep. 2021 That lets the pilot project avoid having to source rare, radioactive tritium and deal with the excess heat and generated radioactivity. Daniel Clery, Science | AAAS, 16 June 2021 Her work on rare particle searches intertwines with that of chemists tracing radioactivity. Karmela Padavic-callaghan, Scientific American, 10 May 2021

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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Dictionary Entries Near radioactivity

radioactive series

radioactivity

radioallergosorbent

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Statistics for radioactivity

Last Updated

17 Nov 2021

Cite this Entry

“Radioactivity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radioactivity. Accessed 7 Dec. 2021.

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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

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