theory
gb/θˈiɚi/ us/θˈiɚi/
B1
English
~ 700
elmélet, tudományos elmélet, elméleti keret, feltevés, sejtés
NOUN
B2
1
elmélet
B1
Usage pattern:
a theory about [something]
Einstein's theory of relativity changed our understanding of space and time.
Einstein relativitáselmélete megváltoztatta a térről és az időről alkotott képünket.
The theory explains how galaxies form.
Az elmélet megmagyarázza, hogyan alakulnak ki a galaxisok.
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.
Learner examples
I read about a new theory in science class.
A természettudomány-órán olvastam egy új elméletről.
Her theory is that plants grow faster in sunlight.
Az elmélete szerint a növények gyorsabban nőnek napfényben.
The theory says the earth goes around the sun.
Scientists have a theory about why animals migrate.
Common mistake:
Learners sometimes confuse 'theory' with 'hypothesis'. A hypothesis is an idea to be tested; a theory is already supported by evidence.
Meaning
Explanation supported by evidence
Collocations
scientific theory
|develop a theory
|theory suggests
|test a theory
|propose a theory
Synonyms
explanation (More general; can be for everyday situations, not just formal or scientific contexts.)
Antonyms
fact (A fact is something known to be true without the need for explanation or hypothesis.)
Themes
science
|education
|research
|core_vocabulary
Definition
An idea that explains why things happen, based on facts and study.
A well-substantiated explanation of some aspect of the natural or social world, based on a body of evidence and reasoning.
NOUN
B2
2
elmélet
B1
Usage pattern:
theory of [something]
In theory, this plan should save the company money.
Elméletileg ez a terv pénzt takarítana meg a cégnek.
She studies political theory at university.
Politikaelméletet tanul az egyetemen.
The new economic theory challenges traditional views.
According to game theory, players act in their own interest.
Learner examples
In theory, the train should arrive at 8.
Elméletileg a vonatnak 8-kor kellene megérkeznie.
We learned about economic theory in class.
Közgazdasági elméletről tanultunk az órán.
His theory is that people are happier in small towns.
Common mistake:
Learners sometimes use 'in theory' incorrectly to mean 'probably' instead of 'according to the plan or idea'.
Meaning
General ideas or principles
Collocations
political theory
|economic theory
|management theory
|in theory
Synonyms
principle (Refers to a basic truth or rule; may be more fixed than 'theory'.)
Antonyms
practice (Refers to the actual doing of something, as opposed to the ideas about it.)
Themes
philosophy
|education
|work
|core_vocabulary
Definition
An idea or set of rules about how something works or should work.
A set of general ideas or principles intended to explain or guide how something works or should be done, not necessarily proven.
NOUN
B1
3
Usage pattern:
have a theory that [clause]
I have a theory that my neighbor is avoiding me.
Az a feltevésem, hogy a szomszédom kerül engem.
Her theory is that the cat goes out at night to hunt.
Az a feltevése, hogy a macska éjszaka kijár vadászni.
There's a popular conspiracy theory about that event.
Learner examples
I have a theory that it will rain today.
Az a sejtésem, hogy ma esni fog.
His theory is that she is tired.
Az a sejtése, hogy a lány fáradt.
They talk about a strange conspiracy theory.
Common mistake:
Learners may overuse 'theory' for casual guesses; 'idea' or 'guess' can be more natural in informal speech.
Meaning
Unproven belief or guess
Collocations
have a theory
|my theory is that
|conspiracy theory
Synonyms
speculation (More formal; often suggests guessing without strong evidence.)
Antonyms
certainty (Something known for sure, without doubt.)
Themes
daily life
|communication
|core_vocabulary
Definition
A guess or idea that might explain something, but is not certain.
An idea or guess about something that may explain it, but is not yet proven.
Grammar
Dictionary form
theory
IPA
GB/θˈiɚi/
US/θˈiɚi/
Syllables & stress
the - ory (2 syllables)
Stress on 1st syllable (the)
Word forms
Noun
- Base: theory
- Plural: theories, theory
Word family
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.
Examples
- 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.
Examples
- 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.
Examples
- 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.