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

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That banana was likely to have been introduced by scientists who ate the fruit and handled the samples, or by those who manufactured the reagents. Quanta Magazine, "Ancient DNA Yields Snapshots of Vanished Ecosystems," 29 May 2019 Back at Blue Water’s offices in Remington, Volpitta mixed the harbor samples with a reagent used to reveal enterococcus bacteria and poured them into trays kind of like ice cube trays. Scott Dance,, "Sampling initiative in Baltimore's Inner Harbor aims to answer the question, 'How's the water, hon?'," 25 June 2019 After excavation, the ore would be crushed and washed with water and reagents to concentrate the copper and molybdenum. Douglas Main, National Geographic, "In a land of wild cats and scarce water, a battle over mining heats up," 25 Apr. 2019 But the lab itself is palatial: two stories of white brick walls, industrial kitchen counters marked with dry-erase notes, shelves towering with glassware and reagents. Emily Baumgaertner, New York Times, "As D.I.Y. Gene Editing Gains Popularity, ‘Someone Is Going to Get Hurt’," 14 May 2018 But the process, which uses a series of toxic organic reagents, is typically slow and error-prone, limiting oligos to about 200 letters—a tiny fraction of the thousands of letters that make up most genes. Robert F. Service, Science | AAAS, "New technique could help scientists create a gene in just 1 day," 18 June 2018 But early into the rover’s mission, researchers discovered that carbon-rich chemical reagents were leaking out of some of SAM’s components, potentially contaminating nearby samples. Adam Mann, Scientific American, "Curiosity Rover Uncovers Long-Sought Organic Materials on Martian Surface," 7 June 2018 Some reserve their reagents exclusively for their own patients, unless public blood banks call directly and offer other scarce products in exchange for them. Rachelle Krygier, Washington Post, "Venezuela faces a terrible new crisis: A critical shortage of blood," 8 Mar. 2018 After the order is completed, software directs compressors and pumps to push chemical reagents into the rows of instruments, mixing the fluids and catalyzing the 100,000 reactions needed to create a single batch of kits. Megan Molteni, WIRED, "Biology Will Be the Next Great Computing Platform," 3 May 2018

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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Last Updated

14 Jul 2019

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Time Traveler for reagent

The first known use of reagent was in 1797

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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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