re·​agent | \ rē-ˈā-jənt How to pronounce reagent (audio) \

Definition of reagent

: a substance used (as in detecting or measuring a component, in preparing a product, or in developing photographs) because of its chemical or biological activity

Examples of reagent in a Sentence

Recent Examples on the Web Roche’s test may require one kind of reagent or machine; Abbott’s may require another. Sy Mukherjee, Fortune, "Why COVID-19 testing in the U.S. is still plagued with delays and inconsistencies," 4 Aug. 2020 Some are also running out of the chemical reagent that must react with a testing specimen. Robinson Meyer, The Atlantic, "U.S. Coronavirus Testing Could Fail Again," 30 June 2020 The state placed $60 million in bulk orders of testing reagents. Elizabeth Depompei, The Indianapolis Star, "Coronavirus in Indiana: What we learned Wednesday from the governor's news conference," 10 June 2020 Earlier in the week, DeWine spoke to the Food and Drug Administration and Vice President Mike Pence about approving new reagent made by Thermo Fisher Scientific. Laura Hancock, cleveland, "Ohio coronavirus cases top 15,000: Gov. Mike DeWine’s Friday, April 24 briefing," 24 Apr. 2020 Meanwhile, state officials and hospitals continue to report shortages of swabs, reagents and other supplies needed for testing kits, as well as delays in securing test results. NBC News, "Coronavirus testing must double or triple before U.S. can safely reopen, experts say," 16 Apr. 2020 No need for a mask or goggles: The samples sitting in trays beyond the door had been treated with a chemical reagent that rendered the coronavirus inactive. Washington Post, "24 hours inside the lives upended by coronavirus in the nation’s capital," 2 Apr. 2020 Testing could soon be hampered by a shortage of reagents, caused in part by the disruption of supply chains in Asia, Osterholm notes. Science News Staff, Science | AAAS, "The United States leads in coronavirus cases, but not pandemic response," 1 Apr. 2020 Illinois has three state labs that run tests but Pritzker said not enough tests are available and there is a nationwide shortage of reagent. John Tozzi,, "Coronavirus Testing Gap Creates Public-Health Chaos Across U.S.," 15 May 2020

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

1797, in the meaning defined above

History and Etymology for reagent

New Latin reagent-, reagens, present participle of reagere to react — more at react

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Time Traveler for reagent

Time Traveler

The first known use of reagent was in 1797

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Statistics for reagent

Last Updated

12 Aug 2020

Cite this Entry

“Reagent.” Dictionary, Merriam-Webster, Accessed 15 Aug. 2020.

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More Definitions for reagent


How to pronounce reagent (audio)

English Language Learners Definition of reagent

chemistry : a substance that is used to test for the presence of another substance by causing a chemical reaction with it


re·​agent | \ rē-ˈā-jənt How to pronounce reagent (audio) \

Medical Definition of reagent

1 : a substance used (as in detecting or measuring a component, in preparing a product, or in developing photographs) because of its chemical or biological activity

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