theory
A well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.
In science, a theory is not a guess or a hunch. It is a comprehensive explanation, supported by extensive evidence, that unifies many observations and hypotheses. Examples include the Theory of Evolution or the Theory of Relativity.
Word relationships
- explanation: Explanation is a general term; a theory is a specific type of comprehensive, evidence-based explanation.
- model: A model is often a simplified representation of a theory, used for prediction or understanding.
- framework: Framework is a basic structure of ideas; a theory is a detailed, substantiated framework.
- fact: A fact is an isolated piece of verifiable information; a theory explains a body of facts.
- hypothesis: A hypothesis is a testable proposition; a theory is a well-supported explanation.
Commonly confused with
- hypothesis: A hypothesis is a specific, testable prediction; a theory is a broad, well-supported explanation for a wide range of phenomena.
Word family
- theoretical (adjective): Concerned with or involving the theory of a subject or area of study rather than its practical application.
- theorize (verb): To form a theory or theories about something.
Collocations
- scientific theory
- evolutionary theory
- economic theory
- social theory
- grand theory
Idioms & expressions
- in theory
Example sentences
- "Despite ongoing debate, the theory that the universe originated from a Big Bang is the most widely accepted scientific explanation." The Theory of Evolution is a cornerstone of modern biology.
- "The quantum theory revolutionized our understanding of atomic and subatomic particles." A good scientific theory can make testable predictions.
Memory hook
Think of a 'THEATER' (theory) where a complex play unfolds, representing a well-developed explanation of many events. THEATER-Y: Well-supported explanation.
When not to use
Do not use 'theory' as a casual synonym for 'guess,' 'idea,' or 'speculation.' In scientific contexts, a theory holds significant weight and evidence.
Fun facts
- The common phrase 'it's just a theory' often misrepresents the scientific meaning of 'theory,' implying it's unproven, whereas scientifically it's highly substantiated.
Related words
Explore more words
Theorem, hypothesis, corroborate, empirical, substantiate, paradigm
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