From Longman Dictionary of Contemporary Englishreagentre‧a‧gent /riˈeɪdʒənt/ noun [countable] technical HCa substance that shows that another substance in a compound exists, by causing a chemical reaction
Examples from the Corpus
reagent• Special liquid reagents or tablets are added to a sample of aquarium water.• The necessity for using very high doses of reagents, however, to detect invitro phosphorylation of membranes, is well recognised.• Maintain diagnostic and reference reagents for the identification of emerging pathogens.• The size of the inner diameter regulates the amount of sample, reagents, water, and air pumped into the system.• Here the social reagents of post-war London life had got to work.• Both of these staining reagents were used as directed by the manufacturer's instructions.• The sample is introduced on one side of the membrane, the reagent on the other side.• These reagents, as well as reference procedures for specialized diagnostic and molecular epidemiologic approaches, are usually not produced commercially.Origin reagent (1700-1800) Modern Latin present participle of reagere “to react”, from Latin agere “to act” 