reaction
noun
Simple meaning
A process in which one or more substances are changed into others.
Pronunciation
Say it like this:
reeakshuhnSay the bold part a little louder.
IPA pronunciation (US)
ɹiˈækʃən
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
chemistry
A process in which one or more substances are changed into others
“There was a chemical reaction of the lime with the ground water.”
chemistry
A transformation in which one or more substances is converted into another by combination or decomposition.
An action or statement in response to a stimulus or other event.
Internet
An icon or emoji appended to a posted message by a user to express their feeling about it.
Word at a Glance
- Difficulty
- B1 · Intermediate
- Frequency
- Common
- Typical Use
- Everyday English
Word Aura™
How this word commonly comes across.
Aura for this meaning
This meaning: A process in which one or more substances are changed into others
Used this way, reaction is a specialist word that usually carries little praise or criticism of its own. This is a scientific use: it names something precisely within a field of study, so it appears in research and teaching more than in conversation.
“There was a chemical reaction of the lime with the ground water.”
- Emotional tone
- Neutral
- Formality
- Specialist/technical
- Intensity
- Not strongly marked
- How common
- Specialized
- Connotation
- Clinical and technical
- Usage feel
- Technical and specialized
Where it naturally appears
- Science
- Academic writing
- Technical/specialist writing
Usage note
In general conversation this sense usually needs explaining — outside its field, people reach for a plainer word.
Natural pattern: reaction of …
Word Aura describes common impressions, not a measurement. Tone changes with sentence, speaker, relationship and situation.
More ways to use reaction
- “His style of painting was a reaction against cubism.”noun
- “His reaction to the news was to start planning what to do.”noun
- “He was pleased by the audience's reaction to his performance.”noun
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Common Patterns and Combinations
How this word naturally appears with others.
Word Family
Related forms, grouped by how they connect.
Compound terms
Established multiword terms.
A defense mechanism in which a person unconsciously develops attitudes and behavior that are the opposite of unacceptable repressed desires and impulses and serve to conceal them.
Propulsion that results from the ejection at high velocity of a mass of gas to which the vehicle reacts with an equal and opposite momentum.
A jet or rocket engine based on a form of aerodynamic propulsion in which the vehicle emits a high-speed stream.
The time that elapses between a stimulus and the response to it.
A turbine with blades arranged to develop torque from gradual decrease of steam pressure from inlet to exhaust.
A jet or rocket engine based on a form of aerodynamic propulsion in which the vehicle emits a high-speed stream.
More about this wordSynonyms, forms, origin
Synonyms
Sense: process in which one
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Dictionary data from Wiktionary via the Free Dictionary API. Simple meanings, combinations and word intelligence are built from verified reference data, no AI is used to load this page.