reactant
noun
re·ac·tant
rē-ˈak-tənt 
: 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
Rather than storing unstable reactants in large quantities, the beetle can derive them from a safer metabolic starting point.
—
Scott Travers, Forbes.com, 21 Apr. 2026
The platform is robust, customizable, and designed to keep each metal atom exposed to reactants, a key requirement for maximum catalytic activity.
—Neetika Walter, Interesting Engineering, 3 Dec. 2025
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
The chemical processes are generally most efficient when there’s a constant supply of power and reactants.
—Matthias Mueller, IEEE Spectrum, 19 Aug. 2023
For our purposes, level three (searching) and level four (reactant) are the most relevant.
—Joey Camire, Quartz, 21 Mar. 2020
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Scott Travers, Forbes.com, 21 Apr. 2026
The platform is robust, customizable, and designed to keep each metal atom exposed to reactants, a key requirement for maximum catalytic activity.
—Neetika Walter, Interesting Engineering, 3 Dec. 2025
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
The chemical processes are generally most efficient when there’s a constant supply of power and reactants.
—Matthias Mueller, IEEE Spectrum, 19 Aug. 2023
For our purposes, level three (searching) and level four (reactant) are the most relevant.
—Joey Camire, Quartz, 21 Mar. 2020
Cite this Entry
“Reactant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reactant. Accessed 2 May. 2026.
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reactant
noun
re·ac·tant
rē-ˈak-tənt
: a substance that enters into and is changed by a chemical reaction
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