Definition of 'reaction'
Word forms: plural reactions
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.
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.
5. uncountable noun
Reaction is the belief that the political or social system of your country should not change.
[disapproval]
6. countable noun
A chemical reaction is a process in which two substances combine together chemically to form another substance.
7. countable noun
Collins COBUILD Advanced Learner’s Dictionary. Copyright © HarperCollins Publishers
British English pronunciation
American English pronunciation
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Word Frequency
reaction in British English
noun
▶ 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 incorrect2.
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
5. medicine
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
Collins English Dictionary. Copyright © HarperCollins Publishers
Derived forms
reactional (reˈactional) adjective
Word Frequency
reaction in American English
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.
d.
an increased activity following depression
Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 by
Houghton Mifflin Harcourt. All rights reserved.
Derived forms
reactional (reˈactional)
adjective
Word Frequency
reaction in American English
(riˈækʃən)
noun
1.
a reverse movement or tendency; an action in a reverse direction or manner
2.
movement in the direction of political conservatism or extreme rightism
3.
action in response to some influence, event, etc
the nation's reaction to the President's speech
5. Medicine
a.
the action caused by the resistance to another action
6. Bacteriology & Immunology
7. Chemistry
the reciprocal action of chemical agents upon each other; chemical change
8. Also called: nuclear reaction Physics
9. Mechanics
the instantaneous response of a system to an applied force, manifested as the exertion of a force equal in magnitude but opposite in direction to the applied force
Most material © 2005, 1997, 1991 by Penguin Random House LLC. Modified entries © 2019
by Penguin Random House LLC and HarperCollins Publishers Ltd
Derived forms
reactional adjective
reactionally
adverb
Word origin
[1635–45; re- + action, modeled on react]Examples of 'reaction' in a sentence
reaction
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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 /riˈækʃən/
- 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
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reaction
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Definition of reaction from the Collins English Dictionary
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