Your reaction to something that has happened or something that you have experienced is what you feel, say, or do because of it.
Reaction to the visit is mixed. [+ to]
The initial reaction of most participants is fear.
He was surprised that his answer should have caused such a strong reaction.
2. countable noun
A reaction against something is a way of behaving or doing something that is deliberately different from what has been done before.
All new fashion starts out as a reaction against existing convention. [+ against]
Her three years of freedom seemed like a reaction against that childhood.
Synonyms: counteraction, compensation, backlash, recoil More Synonyms of reaction
3. singular noun
If there is a reaction against something, it becomes unpopular.
Premature moves in this respect might well provoke a reaction against the reform. [+ against]
The idealism may be a reaction against the failure of society to manage itself.
4. plural noun [oft poss NOUN]
Your reactions are your ability to move quickly in response to something, for example when you are in danger.
If his reactions are so slow, he shouldn't be in charge of a bus.
The sport requires very fast reactions.
5. uncountable noun
Reaction is the belief that the political or social system of your country should not change.
[disapproval]
Thus, he aided reaction and thwarted progress.
...their victory against the forces of reaction and censorship.
Synonyms: conservatism, the right, the extreme right, counter-revolution More Synonyms of reaction
6. countable noun
A chemical reaction is a process in which two substances combine together chemically to form another substance.
Ozone is produced by the reaction between oxygen and ultra-violet light.
Catalysts are materials which greatly speed up chemical reactions.
7. countable noun
If you have a reactionto a substance such as a drug, or to something you have touched, you are affected unpleasantly or made ill by it.
Every year, 5000 people have life-threatening reactions to anaesthetics. [+ to]
Common foods which cause this kind of reaction are fish, eggs, and shellfish.
Synonyms: sensitivity, condition, susceptibility, hypersensitivity More Synonyms of reaction
More Synonyms of reaction
reaction in British English
(rɪˈækʃən)
noun
1.
a response to some foregoing action or stimulus
2.
the reciprocal action of two things acting together
3.
opposition to change, esp political change, or a desire to return to a former condition or system
4.
a response indicating a person's feelings or emotional attitude
5. medicine
a.
any effect produced by the action of a drug, esp an adverse effect
Compare side effect
b.
any effect produced by a substance (allergen) to which a person is allergic
6.
the simultaneous equal and opposite force that acts on a body whenever it exerts a force on another body
7. short for chemical reaction, nuclear reaction
8. stock exchange
a sharp fall in price interrupting a general rise
▶ USAGE Reaction is used to refer both to an instant response (her reaction was one of amazement) and to a considered response in the form of a statement (the Minister gave his reaction to the court's decision). Some people think this second use is incorrect
Derived forms
reactional (reˈactional)
adjective
reaction in American English
(riˈækʃən)
noun
1.
a return or opposing action, force, influence, etc.
2.
a response, as to a stimulus or influence
3.
a movement back to a former or less advanced condition, stage, etc.; esp., such a movement or tendency in economics or politics; extreme conservatism
4. Chemistry
a.
the mutual action of substances undergoing chemical change
b.
a process that involves changes within the nucleus of an atom
c.
the state resulting from such changes
5. Medicine
a.
an action induced by resistance to another action
b.
the effect produced by an allergen
c.
a depression or exhaustion of energy following nervous tension, overstimulation, etc.
d.
an increased activity following depression
6. Physiology and Psychology
an organic response to a stimulus
Derived forms
reactional (reˈactional)
adjective
COBUILD Collocations
reaction
angry reaction
audience reaction
crowd reaction
emotional reaction
extreme reaction
furious reaction
gauge reaction
hostile reaction
hysterical reaction
instant reaction
instinctive reaction
knee-jerk reaction
muted reaction
natural reaction
negative reaction
normal reaction
positive reaction
prompt a reaction
quick reaction
spark a reaction
stress reaction
suffer a reaction
trigger a reaction
Examples of 'reaction' in a sentence
reaction
You are more likely to get an understanding reaction.
The Sun (2016)
The news was met with a mixed reaction.
Times, Sunday Times (2016)
We also met a retired mum of two in her sixties who says she also suffers an adverse reaction to the pesticides.
The Sun (2016)
When we eat, all kinds of chemical reactions take place in our bodies.
The Sun (2016)
Although their reaction times slow, they take more care.
The Sun (2016)
The government 's reaction has hardly reassured critics of its commitment to free speech or the interests of business.
Times, Sunday Times (2016)
What was your initial reaction?
The Sun (2016)
He said:'I understand all the different reactions.
The Sun (2016)
Anyone with a heart condition, blood pressure problems, epilepsy or asthma can have a very dangerous reaction to the drug.
The Sun (2017)
He has said that his initial reaction was disappointment.
Times, Sunday Times (2012)
Were you shocked by the force of the reaction to it?
Times, Sunday Times (2009)
It was a noble move but my reaction was one of deep regret.
The Sun (2013)
What causes ulcers in one person may result in no reaction at all in another.
Chaitow, Leon The Beat Fatigue Workbook - how to identify the causes (1988)
Others will fear the reactions of those around them.
Carpenter, Anne & Johnson, Geoffrey Why am I Afraid to Grieve (1994)
The pictures provoked a furious reaction yesterday.
Times, Sunday Times (2014)
What was noticeably different was the reaction to the performance itself.
Times, Sunday Times (2008)
She spoke in a hushed voice and had a slow reaction time in tests.
Times, Sunday Times (2013)
The police reaction was well over the top.
The Sun (2007)
The basic unit of a compound is the molecule whose formation requires a chemical reaction.
McCahill, T. A. Biology Basic Facts (1982)
Until now adverse reactions were blamed on the drug.
Holford, Patrick The Family Nutrition Workbook (1988)
Your reaction may be caused by one of them.
Brumberg, Elaine Take Care of Your Skin (1990)
These hairs contain toxins that cause skin irritation and allergic reactions.
Times, Sunday Times (2016)
It is just an extreme form of stress reaction.
Hambly, Dr Kenneth Banish Anxiety - how to stop worrying and take charge of your life (1991)
Your quietly confident attitude to love gets the hottest reaction from a partner.
The Sun (2011)
This is a very curious and strong reaction.
Times, Sunday Times (2006)
Your reaction to the changes of the weeks just past is very different from theirs.
Times, Sunday Times (2007)
The tests also assess how genes affect your reactions to common drugs.
Times, Sunday Times (2010)
The plan has met with mixed reactions.
Times, Sunday Times (2015)
This will trigger chemical reactions in your body that will make you feel the way you felt then.
Times, Sunday Times (2008)
The initial public reaction was lukewarm.
The Times Literary Supplement (2010)
This seems to have produced no noticeable reaction from the Government.
Times, Sunday Times (2006)
First, Soviet history is one of cycles of reform and reaction.
Abshire, David M. Preventing World War III - A Realistic Grand Strategy (1988)
In other languages
reaction
British English: reaction /rɪˈækʃən/ NOUN
Your reaction to something that has happened or something that you have experienced is what you feel, say, or do because of it.
Reaction to the President's visit has been mixed.
American English: reaction
Arabic: تَفَاعُل
Brazilian Portuguese: reação
Chinese: 反应
Croatian: reakcija
Czech: reakce
Danish: reaktion
Dutch: reactie
European Spanish: reacción respuesta
Finnish: reaktio
French: réaction
German: Reaktion
Greek: αντίδραση
Italian: reazione
Japanese: 反応
Korean: 반응
Norwegian: reaksjon
Polish: reakcja
European Portuguese: reação
Romanian: reacție
Russian: реакция
Latin American Spanish: reacción
Swedish: reaktion
Thai: ปฏิกิริยา
Turkish: tepki
Ukrainian: реакція
Vietnamese: sự phản ứng
All related terms of 'reaction'
dark reaction
the stage of photosynthesis involving the reduction of carbon dioxide and the dissociation of water, using chemical energy stored in ATP : does not require the presence of light
gut reaction
a reaction to a situation derived from a person's instinct and experience
reaction rate
The reaction rate is the speed at which a reaction happens , measured by the speed at which the feed is consumed or the speed at which the product is formed.
reaction time
the lapse of time between stimulation and the beginning of the response
skin reaction
an irritation or inflammation of the skin due to an allergy or infection , brought about by natural means or by a skin test
angry reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
chain reaction
A chain reaction is a series of chemical changes , each of which causes the next.
crowd reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
gauge reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
light reaction
the stage of photosynthesis during which light energy is absorbed by chlorophyll and transformed into chemical energy stored in ATP
muted reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
normal reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
panic reaction
a widespread and excessive response of panic
quick reaction
Your reactions are your ability to move quickly in response to something, for example when you are in danger .
reaction engine
an engine , such as a jet or rocket engine, that ejects gas at high velocity and develops its thrust from the ensuing reaction
stress reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
acrosome reaction
the release of enzymes from the acrosome when a spermatozoon encounters the ovum , allowing fusion with the ovum in the sexual reproductive process
audience reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
chemical reaction
a process that involves changes in the structure and energy content of atoms , molecules , or ions but not their nuclei
emotional reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
extreme reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
Feulgen reaction
a reaction in which an aldehyde combines with a modified Schiff's reagent to produce a purplish compound: used especially to test for the presence of DNA
furious reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
hostile reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
instant reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
insulin reaction
the condition in a diabetic resulting from an overdose of insulin , causing a sharp drop in the blood sugar level with tremor , profuse sweating , and convulsions
natural reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
negative reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say, or do because of it.
nuclear reaction
a process in which the structure and energy content of an atomic nucleus are changed by interaction with another nucleus or particle
positive reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
reaction chamber
the chamber in a rocket engine in which the reaction or combustion of fuel occurs
reaction formation
a defence mechanism by which a person at a conscious level condemns a repressed wish
reaction turbine
a turbine in which the working fluid is accelerated by expansion in both the static nozzles and the rotor blades . Torque is produced by the momentum changes in the rotor and by reaction from fluid accelerating out of the rotor
heat of reaction
the heat evolved or absorbed when one mole of a product is formed at constant pressure
hysterical reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
instinctive reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
knee-jerk reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
prompt a reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
spark a reaction
Your reaction to something that has happened or something that you have experienced is what you feel, say , or do because of it.
suffer a reaction
If you have a reaction to a substance such as a drug, or to something you have touched , you are affected unpleasantly or made ill by it.
thermonuclear reaction
a nuclear fusion reaction occurring at a very high temperature : responsible for the energy produced in the sun , nuclear weapons , and fusion reactors
trigger a reaction
Your reaction to something that has happened or something that you have experienced is what you feel , say , or do because of it.
adverse drug reaction
An adverse drug reaction is a harmful effect associated with the use of a medication at a normal dosage .
Diels-Alder reaction
a type of chemical reaction in which one organic compound containing conjugated double bonds adds to another containing an ethylenic bond to form a product containing a ring
rapid reaction force
a force that can be deployed swiftly to a site of conflict or potential conflict
fight-or-flight reaction
the response of the sympathetic nervous system to a stressful event, preparing the body to fight or flee , associated with the adrenal secretion of epinephrine and characterized by increased heart rate, increased blood flow to the brain and muscles, raised sugar levels, sweaty palms and soles , dilated pupils , and erect hairs
polymerase chain reaction
a technique in which a known DNA sequence is synthesized at high temperatures by means of a polymerase , producing millions of copies for statistical analysis : used in → DNA fingerprinting, in detecting minute quantities of cancer cells, etc.
immune response
the reaction of an organism's body to foreign materials ( antigens ), including the production of antibodies
conversion
Conversion is the act or process of changing something into a different state or form.
He showed no reaction when the judge pronounced his sentence.
Synonyms
response
There has been no response to his remarks.
acknowledgment
Grateful acknowledgement is made for permission to reprint.
feedback
answer
Without waiting for an answer, he turned and went in.
reply
They went ahead without waiting for a reply.
2 (noun)
Definition
any action resisting another
All new fashion starts out as a reaction against existing convention.
Synonyms
counteraction
compensation
backlash
a right-wing backlash
recoil
His reaction was as much a rebuff as a physical recoil.
counterbalance
counterpoise
3 (noun)
Definition
opposition to change
their victory against the forces of reaction and conservatism
Synonyms
conservatism
the right
the extreme right
counter-revolution
obscurantism
4 (noun)
Definition
any effect produced by a drug or by a substance (allergen) to which a person is allergic
Common foods which cause this kind of reaction are fish, eggs and shellfish.
Synonyms
sensitivity
an atmosphere of extreme sensitivity over the situation
condition
susceptibility
She has difficulty dining out because of her susceptibility to smells.
hypersensitivity
allergic effect
(plural noun)
Definition
someone's ability to act in response to something that happens
The sport requires very fast reactions.
Synonyms
reflexes
Usage note
Some people say that reaction should always refer to an instant response to something (as in his reaction was one of amazement), and that this word should not be used to refer to a considered response given in the form of a statement (as in the Minister gave his reaction to the court's decision). Use response instead.
Additional synonyms
in the sense of acknowledgment
Definition
something done or given as an expression of gratitude
Grateful acknowledgement is made for permission to reprint.
Synonyms
appreciation,
answer,
thanks,
credit,
response,
reply,
reaction,
recognition,
gratitude,
indebtedness,
thankfulness,
gratefulness
in the sense of answer
Definition
a reaction or response
Without waiting for an answer, he turned and went in.
Synonyms
reply,
response,
reaction,
resolution,
explanation,
plea,
comeback,
retort,
report,
return,
defence,
acknowledgement,
riposte,
counterattack,
refutation,
rejoinder
in the sense of backlash
Definition
a sudden and adverse reaction
a right-wing backlash
Synonyms
reaction,
response,
resistance,
resentment,
retaliation,
repercussion,
counterblast,
counteraction,
retroaction
Synonyms of 'reaction'
reaction
Explore 'reaction' in the dictionary
Additional synonyms
in the sense of recoil
Definition
the act of recoiling
His reaction was as much a rebuff as a physical recoil.
Synonyms
jerking back,
reaction,
pulling back,
flinching,
quailing,
springing back
in the sense of reply
Definition
an answer or response
They went ahead without waiting for a reply.
Synonyms
answer,
response,
reaction,
counter,
echo,
comeback (informal),
retort,
retaliation,
acknowledgment,
riposte,
counterattack,
return,
rejoinder,
reciprocation
in the sense of susceptibility
Definition
the quality or condition of being easily affected or influenced by something
She has difficulty dining out because of her susceptibility to smells.