noun · academic

theory

UK/ˈθɪəri/US/ˈθiəri/THE·o·ry

Band 4-5speakingtask2

an idea or set of ideas intended to explain something, based on evidence and reasoning

Examples

Einstein's theory of relativity changed physics.

The theory predicts that temperature will affect the reaction speed.

In science, a theory is supported by many experiments and observations.

Band 8 sentence

Although widely accepted, the theory still requires further empirical testing to confirm its predictions.

Collocations

  • scientific theory
  • support a theory
  • develop a theory

Word family

theoretical adjectivetheorize verbtheorist noun

Common mistakes

I have a theory about why he left.I have an idea about why he left.

In theoryly, this should work.Theoretically, this should work.

Say it for a higher band

5idea6explanation7+theory

Synonyms

idea

model

Easily confused

idea

His theory about language learning is supported by many studies.

Related words

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In Science & Research

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