reagent

noun

re·​agent rē-ˈā-jənt How to pronounce reagent (audio)
: 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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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Potential applications include research reagents, industrial enzymes, diagnostic materials and food ingredients. — Alexandra Harrell, Footwear News, 23 Oct. 2026 However, traditional hydrometallurgical plants consume large volumes of one-time chemical reagents. — Aman Tripathi, Interesting Engineering, 2 Sep. 2026 Because no agency oversees production, the conversion process leaves residual solvents, unreacted reagents, and byproducts nobody has characterized. — Jesse M. Pines, Forbes.com, 6 Aug. 2026 Radiological weapons can be detected by a Geiger counter, while chemical weapons can usually be identified by reagents, electronic sensors, and special detection sheets sensitive to things like nerve agents. — David Szondy june 27, New Atlas, 27 June 2026 See All Example Sentences for reagent

Word History

Etymology

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

First Known Use

1797, in the meaning defined above

Time Traveler
The first known use of reagent was in 1797

Phrases Containing reagent

Rhymes for reagent

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Browse Nearby Words

reagency
reagent
reaggregate
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Cite this Entry

“Reagent.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reagent. Accessed 27 Oct. 2026.

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Medical Definition

reagent

noun
re·​agent rē-ˈā-jənt How to pronounce reagent (audio)
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
2
: reactor sense 1b

More from Merriam-Webster on reagent

Britannica.com: Encyclopedia article about reagent

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