Word
reactive
Phoneticsre·ac·tive, stress on the second syllable
US/ɹiˈæktɪv/
UK/ɹɪˈæktɪv/
Definitions
01responding to events
B2 · Upper Intermediate
adj. acting only after something has happened, rather than planning for it before it happens.
adj. characterised by a tendency to respond to events after they occur rather than initiating proactive measures.
“The company was too reactive and only fixed the problem after customers complained.”
“A reactive management style often leads to crisis-driven decision-making, whereas a proactive approach identifies potential risks before they manifest as systemic failures.”
Synonyms
Antonyms
02chemical change
C1 · Advanced Science Technical
adj. describing a substance that changes easily when it comes into contact with another substance.
adj. readily taking part in chemical reactions; having a high degree of chemical activity.
“Potassium is a highly reactive metal that must be stored in oil.”
“The laboratory technician warned that the compound was extremely reactive when exposed to even trace amounts of atmospheric moisture.”
03electrical circuits
C2 · Proficiency Science Technical
adj. related to parts of an electric circuit that store energy instead of just letting it flow through.
adj. pertaining to a circuit or component characterised by induction or capacitance rather than pure resistance.
“The engineer measured the reactive power to check the efficiency of the motor.”
“In AC power systems, reactive loads can cause the voltage and current to fall out of phase, necessitating the use of capacitors for power factor correction.”
Antonyms
Real-World Examples
“Most are reactive: A guest asks when breakfast starts, and the chatbot provides the answer.” “We probably cannot build a completely pothole-free future, but we can move from reactive repair toward predicting and preventing them more effectively.” Etymology
From react + -ive.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Word family
VERB
ADJECTIVE
Domains
- 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.B2 FirstIELTSIELTSInternational English Language Testing SystemThe 0–9 band test co-owned by the British Council, IDP, and Cambridge. Used for university entry, work, and migration.5.5–6.5TOEFL 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: 4.0–4.572–94TOEICTOEICTest of English for International CommunicationETS's workplace English test, big in Japan and Korea. Listening & Reading scores 10–990 and tops out at C1.785–944
- Frequency
- Frequent
- Level
- B2 · Upper Intermediate
- Updated
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englishreference.com/q/reactive