reagent

American  

[ree-ey-juhnt] / riˈeɪ dʒənt /

noun

Chemistry.

1. a substance that, because of the reactions it causes, is used in analysis and synthesis.

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reagent British  

/ riːˈeɪdʒənt /

noun

1. a substance for use in a chemical reaction, esp for use in chemical synthesis and analysis

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reagent Scientific  

/ rē-ā′jənt /

1. A substance participating in a chemical reaction, especially one used to detect, measure, or produce another substance.

2. Compare agent

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Etymology

Origin of reagent

1790–1800; re(act) + agent; act

Example Sentences

Elevated diesel prices will drive up costs of everything from contract mining, consumables, reagent freight and contract haulage to export logistics, shipping and mine-site aviation, it says.

From The Wall Street Journal • Mar. 30, 2026

But a blood enhancement chemical reagent uncovered a footwear mark and drag mark on the floor.

From BBC • Mar. 7, 2026

The researchers utilized potassium xanthate instead of hydrogen sulfide, owing to its better reactivity in aryne reactions and pentafluorophenyl bromide as an electrophilic brominating reagent.

From Science Daily • May 23, 2024

Erb’s team set out to devise a simpler approach, creating the “AAA cycle” in which four enzymes in solution harness electricity and use it to convert ADP, added as a reagent, into ATP.

From Science Magazine • Aug. 22, 2023

Apparently Natalie didn’t know what a reagent was either.

From "The Strangers" by Margaret Peterson Haddix