Simple Definition of reagent

from our Learner's Dictionary

reagent

noun

riˈeɪʤənt How to pronounce reagent (audio)
plural reagents
chemistry : a substance that is used to test for the presence of another substance by causing a chemical reaction with it

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“Reagent.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/reagent. Accessed 18 Jun. 2026.

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