Word
reagent
US/ˈɹidʒənt/
UK/ɹɪˈeɪdʒənt/
Definition
n. a substance used in a chemical test or experiment to cause a reaction. It helps you see if another substance is present or how it behaves.
n. a substance that is added to another substance to cause a chemical reaction. Often used in qualitative analysis to identify the presence of specific ions or compounds.
Examples
“The student added a few drops of the reagent to the solution.”
“In the lab, the technician used a specific reagent to detect the presence of chloride ions in the water sample.”
“The chemist carefully selected a reagent that would react selectively with the target molecule without interfering with the surrounding organic structure.”
Examples
simple
“The student added a few drops of the reagent to the solution.”
contextual
“In the lab, the technician used a specific reagent to detect the presence of chloride ions in the water sample.”
complex
“The chemist carefully selected a reagent that would react selectively with the target molecule without interfering with the surrounding organic structure.”
Real-World Examples
“When the chlorinating reagent was omitted, the starting material was recovered unchanged.” “The result contradicted the intuitive expectation that more reagent would yield better performance.” Etymology
Possibly from Latin reagō. Compare with Norwegian Bokmål reagens. The sequence of act → action → agent → agency shows morphologic and semantic parallel, and apparent cognate relation, with react → reaction → reagent → reagency.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Domain
- Exam level
- CambridgeCambridgeCambridge English QualificationsThe exam suite from Cambridge University Press & Assessment, from A1 Movers up to C2 Proficiency. The benchmark names double as CEFR labels.C1 AdvancedIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.7.0–8.0TOEFL iBTTOEFL iBTTest of English as a Foreign Language, Internet-Based TestETS's academic English test, the standard route for US university admissions. Scored 0–120, with a 1–6 scale since 2026.1–6 scale: 5.0–5.595–113TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.945–990
- Frequency
- Occasional
- Level
- C1 · Advanced
- Updated
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QR code
englishreference.com/q/reagent