ir·​ra·​di·​a·​tion | \ i-ˌrā-dē-ˈā-shən How to pronounce irradiation (audio) \

Definition of irradiation

1 : exposure to radiation (such as X-rays or alpha particles)
2 : the application of radiation (such as X-rays or gamma rays) for therapeutic purposes or for sterilization (as of food) also : partial or complete sterilization by irradiation

Examples of irradiation in a Sentence

Recent Examples on the Web

Prions can withstand heat, irradiation, enzymes that normally degrade proteins, and protein-altering chemicals, such as formaldehyde. Beth Mole, Ars Technica, "Camels in Africa may have been quietly spreading prion disease for decades," 26 Apr. 2018 That calculated out to an unpleasant irradiation rate of 5.75 micros an hour. Aaron Gilbreath, Longreads, "As Innocuous as Plant No. 1," 10 Apr. 2018 Private companies then rent irradiation time at the reactors, send the resulting medley of isotopes to processing plants, book the final Mo-99 on commercial flights back to the US, and distribute it to hospitals and pharmacies. Beth Mole, Ars Technica, "Scientists racing to save vital medical isotopes imperiled by shabby reactors," 17 Jan. 2018 Crops are generally grown without synthetic pesticides, artificial fertilizers, irradiation (a form of radiation used to kill bacteria), or biotechnology. Jessica Decostole, Redbook, "5 Things You Should Know About Organic Food," 29 Nov. 2017 Before its 21-year-old gears gave out, the machine’s cobalt source had become so weak that irradiation sessions meant to last minutes took an hour. Donald G. Mcneil Jr., New York Times, "As Cancer Tears Through Africa, Drug Makers Draw Up a Battle Plan," 7 Oct. 2017 The diamondback moths are not irradiated, though, because the irradiation strategy didn’t work. Sarah Zhang, The Atlantic, "Genetically Modified Moths Come to New York," 8 Sep. 2017 Many in the food-safety camp are already keen on more-energetic kill steps, such as irradiation, chemical treatment with ozone or chlorine compounds, or the use of high-barometric-pressure systems. Holman W. Jenkins, WSJ, "Chipotle Seeks a ‘Kill Step’," 28 July 2017 Instead, Hanford researchers in the late 1960s went to a local prison and paid the inmates to allow the irradiation of their testicles, to see just how much radiation a man can receive before the tails fall from his sperm. Michael Lewis, The Hive, "Why the Scariest Nuclear Threat May Be Coming from Inside the White House," 2 Aug. 2017

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

1901, in the meaning defined at sense 1

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Time Traveler for irradiation

The first known use of irradiation was in 1901

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ir·​ra·​di·​a·​tion | \ i-ˌrā-dē-ˈā-shən How to pronounce irradiation (audio) \

Kids Definition of irradiation

: exposure to radiation


ir·​ra·​di·​a·​tion | \ ir-ˌād-ē-ˈā-shən How to pronounce irradiation (audio) \

Medical Definition of irradiation

1a : the radiation of a physiologically active agent from a point of origin within the body especially : the spread of a nerve impulse beyond the usual conduction path
b : apparent enlargement of a light or bright object or surface when displayed against a dark background
2a : exposure to radiation (as X-rays or alpha particles)
b : application of radiation (as X-rays or gamma rays) for therapeutic purposes or for sterilization (as of food)

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More from Merriam-Webster on irradiation

Rhyming Dictionary: Words that rhyme with irradiation

Spanish Central: Translation of irradiation

Nglish: Translation of irradiation for Spanish Speakers Encyclopedia article about irradiation

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