Definition of theory
- the wave theory of light
- her method is based on the theory that all children want to learn
- in theory, we have always advocated freedom for all
- theory of equations
- music theory
a widely accepted scientific theory
Her method is based on the theory that all children want to learn.
There are a number of different theories about the cause of the disease.
She proposed a theory of her own.
Investigators rejected the theory that the death was accidental.
There is no evidence to support such a theory.
He is a specialist in film theory and criticism.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'theory.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
There are many shades of meaning to the word theory. Most of these are used without difficulty, and we understand, based on the context in which they are found, what the intended meaning is. For instance, when we speak of music theory we understand it to be in reference to the underlying principles of the composition of music, and not in reference to some speculation about those principles.
However, there are two senses of theory which are sometimes troublesome. These are the senses which are defined as “a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena” and “an unproven assumption; conjecture.” The second of these is occasionally misapplied in cases where the former is meant, as when a particular scientific theory is derided as "just a theory," implying that it is no more than speculation or conjecture. One may certainly disagree with scientists regarding their theories, but it is an inaccurate interpretation of language to regard their use of the word as implying a tentative hypothesis; the scientific use of theory is quite different than the speculative use of the word.
First Known Use: 1592See Words from the same year
: an idea or set of ideas that is intended to explain facts or events
: an idea that is suggested or presented as possibly true but that is not known or proven to be true
: the general principles or ideas that relate to a particular subject
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Confusing Words—A Quiz