reactant

noun

re·​ac·​tant rē-ˈak-tənt How to pronounce reactant (audio)
: a substance that enters into and is altered in the course of a chemical reaction

Examples of reactant in a Sentence

Recent Examples on the Web
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.
Like Pac-Man, this domain closes around reactants and reopens to release products. Priyanka Naik, The Conversation, 7 Mar. 2025 The compartments formed by a matrix and a membrane crucially provide a stable environment that can concentrate reactants and protect them from the external environment, allowing the necessary chemical reactions to take place. Discover Magazine, 17 Oct. 2024 As illustrated by this simplified diagram of the human metabolome (where lines indicate chemical reactions and dots indicate reactants or products), your metabolic network is incredibly complex. Travis Nemkov, Discover Magazine, 11 Apr. 2024 The chemical processes are generally most efficient when there’s a constant supply of power and reactants. Matthias Mueller, IEEE Spectrum, 19 Aug. 2023 Their expertise ensures proper handling of reactants, precise control of reaction conditions, and the ability to troubleshoot any unexpected challenges that may arise. Amber Smith, Discover Magazine, 9 July 2023 According to one study, there are actually five levels of boredom: indifferent, calibrating, searching, reactant, and apathetic. Joey Camire, Quartz, 21 Mar. 2020 For our purposes, level three (searching) and level four (reactant) are the most relevant. Joey Camire, Quartz, 21 Mar. 2020 The Chinese scientists added polyethylene glycol into the reactant mix when building their COF compound, which effectively bridged the porous spaces to create a version that was much more compact and flexible. Jennifer Ouellette, Ars Technica, 21 July 2019

Word History

First Known Use

1916, in the meaning defined above

Time Traveler
The first known use of reactant was in 1916

Browse Nearby Words

Cite this Entry

“Reactant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reactant. Accessed 13 Mar. 2025.

Kids Definition

reactant

noun
re·​ac·​tant rē-ˈak-tənt How to pronounce reactant (audio)
: a substance that enters into and is changed by a chemical reaction

Medical Definition

reactant

noun
re·​ac·​tant -tənt How to pronounce reactant (audio)
: a substance that enters into and is altered in the course of a chemical reaction
reactant adjective

More from Merriam-Webster on reactant

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!