theory
gb/θˈiɚi/ us/θˈiɚi/
B1
Anglais
~ 700
Sens
0 sens
Nom
B2
entity
1
Explanation supported by evidence
An idea that explains why things happen, based on facts and study.
Schéma d’usage :
a theory about [something]
Erreur fréquente :
Learners sometimes confuse 'theory' with 'hypothesis'. A hypothesis is an idea to be tested; a theory is already supported by evidence.
Synonymes
explanation (More general; can be for everyday situations, not just formal or scientific contexts.)
Antonymes
fact (A fact is something known to be true without the need for explanation or hypothesis.)
Collocations
scientific theory
|develop a theory
|theory suggests
|test a theory
|propose a theory
Thèmes
science
|education
|research
|core_vocabulary
Exemples
- Einstein's theory of relativity changed our understanding of space and time.
- The theory explains how galaxies form.
- Her theory is that the missing money was stolen by someone inside the company.
- The researchers developed a new theory to explain the results.
- According to current theory, the universe began with the Big Bang.
Exemples pédagogiques
- I read about a new theory in science class.
- Her theory is that plants grow faster in sunlight.
- The theory says the earth goes around the sun.
- Scientists have a theory about why animals migrate.
Nom
B2
entity
2
General ideas or principles
An idea or set of rules about how something works or should work.
Schéma d’usage :
theory of [something]
Erreur fréquente :
Learners sometimes use 'in theory' incorrectly to mean 'probably' instead of 'according to the plan or idea'.
Synonymes
principle (Refers to a basic truth or rule; may be more fixed than 'theory'.)
Antonymes
practice (Refers to the actual doing of something, as opposed to the ideas about it.)
Collocations
political theory
|economic theory
|management theory
|in theory
Thèmes
philosophy
|education
|work
|core_vocabulary
Exemples
- In theory, this plan should save the company money.
- She studies political theory at university.
- The new economic theory challenges traditional views.
- According to game theory, players act in their own interest.
Exemples pédagogiques
- In theory, the train should arrive at 8.
- We learned about economic theory in class.
- His theory is that people are happier in small towns.
Nom
B1
entity
3
Unproven belief or guess
A guess or idea that might explain something, but is not certain.
Schéma d’usage :
have a theory that [clause]
Erreur fréquente :
Learners may overuse 'theory' for casual guesses; 'idea' or 'guess' can be more natural in informal speech.
Synonymes
speculation (More formal; often suggests guessing without strong evidence.)
Antonymes
certainty (Something known for sure, without doubt.)
Collocations
have a theory
|my theory is that
|conspiracy theory
Thèmes
daily life
|communication
|core_vocabulary
Exemples
- I have a theory that my neighbor is avoiding me.
- Her theory is that the cat goes out at night to hunt.
- There's a popular conspiracy theory about that event.
Exemples pédagogiques
- I have a theory that it will rain today.
- His theory is that she is tired.
- They talk about a strange conspiracy theory.
Grammaire
Forme canonique
theory
API
GB/θˈiɚi/
US/θˈiɚi/
Syllabes et accentuation
the - ory (2 syllabes)
Stress on 1st syllable (the)
Formes du mot
Noun
- Base: theory
- Plural: theories, theory
Famille de mots
Forms
theories
noun
Core family
theoretical
adjective B2
theoretically
adverb B2
Expressions
conspiracy theory
1/kənspˈɪɹəsi θˈiɚi/
fixed phrase
belief about secret harmful plot
An explanation of an event that says a secret group planned it for a bad reason, usually without good proof.
Exemples
- Some people believe the moon landing was a conspiracy theory.
- The internet has made it easier for conspiracy theory videos to reach millions of people.
- The internet has made it easier for conspiracy theories to spread.
- He dismissed the idea that the vaccine is a government plot as a wild conspiracy theory.
- Some conspiracy theory communities moved to new platforms after being banned.
in theory
1/ˈɪn θˈiɚi/
fixed phrase
According to ideas or plans
When something should happen based on ideas or plans, but it might not happen in real life.
Exemples
- In theory, this method should work every time.
- In theory, the plan should work perfectly.
- In theory, anyone can apply for the job, but few are qualified.
- In theory, anyone can apply for the job, but in practice it’s very competitive.
in theory
2/ˈɪn θˈiɚi/
fixed phrase
according to theory, not practice
According to ideas or rules of how something should work, not necessarily how it really works.
Exemples
- In theory, the new law will reduce traffic, but many people doubt it.
- The plan sounds perfect in theory, but it will be hard to carry out.
- In theory, children learn faster with smaller classes.