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theory

Pronunciation: /ˈθɪəri/

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Definition of theory

noun (plural theories)

a supposition or a system of ideas intended to explain something, especially one based on general principles independent of the thing to be explained:Darwin’s theory of evolution
a set of principles on which the practice of an activity is based:a theory of education [mass noun]:music theory
an idea used to account for a situation or justify a course of action:my theory would be that the place has been seriously mismanaged
Mathematics a collection of propositions to illustrate the principles of a subject.

Phrases

in theory: used in describing what is supposed to happen or be possible, usually with the implication that it does not in fact happen:in theory, things can only get better; in practice, they may well become a lot worse

Origin:

late 16th century (denoting a mental scheme of something to be done): via late Latin from Greek theōria 'contemplation, speculation', from theōros 'spectator'

theory in other Oxford dictionaries

Definition of theory in the US English dictionary

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Other

theory

noun (plural theories)

Phrases

in theory

Origin:

theory in other Oxford dictionaries

Nearby words

More results for theory

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