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The following statistics are based on the British National Corpus, so they are representative for the British English.

Usage statistics for the noun theory:

spoken English17.94%written English82.06% imaginative writing11.55%informational writing88.45%

Distribution of usage frequency for the most common synonyms of the noun theory:


The word theory and its family (theoretical, theoretically, theories, theorist, theorists) are included in the Academic Word List by Dr. Averil Coxhead, which contains the 570 most frequent word families used in academic texts from a variety of subject areas, of interest for students that learn the words most needed to study at tertiary institutions.

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Definition of the noun theory

What does theory mean as a name of something?

Theory is one of the top 1000 most common nouns. It is used mostly in informational writing, being one of the top 1000 most common nouns in informational written English.

noun - plural: theories

  1. a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena
    • example: true in fact and theory
    • lexical domain: Cognitive Processes - nouns denoting cognitive processes and contents
    • more generic word: explanation = thought that makes something comprehensible
    • more specific terms:
      • reductionism = a theory that all complex systems can be completely understood in terms of their components
      • blastogenesis = theory that inherited characteristics are transmitted by germ plasm
      • theory of preformation / preformation = a theory (popular in the 18th century and now discredited) that an individual develops by simple enlargement of a tiny fully formed organism (a homunculus) that exists in the germ cell
      • scientific theory = a theory that explains scientific observations
      • field theory = a theory that explains a physical phenomenon in terms of a field and the manner in which it interacts with matter or with other fields
      • economic theory = a theory of commercial activities
      • atomistic theory / atomist theory / atomic theory / atomism = any theory in which all matter is composed of tiny discrete finite indivisible indestructible particles
      • holistic theory / holism = the theory that the parts of any whole cannot exist and cannot be understood except in their relation to the whole
      • structural sociology / structuralism = a sociological theory based on the premise that society comes before individuals
      • structural anthropology / structuralism = an anthropological theory that there are unobservable social structures that generate observable social phenomena
    • parts:
  2. a tentative insight into the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena
    • examples: a scientific hypothesis that survives experimental testing becomes a scientific theory | he proposed a fresh theory of alkalis that later was accepted in chemical practices
    • lexical domain: Cognitive Processes - nouns denoting cognitive processes and contents
    • synonyms of theory: hypothesis / possibility
    • more generic words: concept / conception / construct = an abstract or general idea inferred or derived from specific instances
    • more specific terms:
  3. a belief that can guide behavior
    • examples: the architect has a theory that more is less | they killed him on the theory that dead men tell no tales
    • lexical domain: Cognitive Processes - nouns denoting cognitive processes and contents
    • more generic word: belief = any cognitive content held as true
    • more specific words:
      • egoism = the theory that the pursuit of your own welfare in the basis of morality
      • hodgepodge / patchwork / jumble = a theory or argument made up of miscellaneous or incongruous ideas

Alternative definition of the noun theory


  1. [context: countable, proscribed] An unproven conjecture.
  2. [uncountable] An expectation of what should happen, barring unforeseen circumstances.
  3. [countable] [science] A coherent statement or set of statements that attempts to explain observed phenomena.
  4. [countable] [science] A logical structure that enables one to deduce the possible results of every experiment that falls within its purview.
  5. [uncountable] [mathematics] A field of study attempting to exhaustively describe a particular class of constructs.
  6. [countable] [logic] A set of axioms together with all statements derivable from them. Equivalently, a formal language plus a set of axioms (from which can then be derived theorems).


Theory is a New York-based men's and women's contemporary fashion label which sells clothes and accessories. Theory merchandise is sold through signature Theory stores and retailers all around the world. The brand is owned by Fast Retailing of Japan.

  • also known as 希爾瑞


"Theory" is a book by Jane Bastien.


  1. "Theory" is a composition.
  2. "Theory" is a composition.


  1. Theory is a contemplative and rational type of abstract or generalizing thinking, or the results of such thinking. Depending on the context, the results might for example include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several different related meanings. A theory is not the same as a hypothesis. A theory provides an explanatory framework for some observation, and from the assumptions of the explanation follows a number of possible hypotheses that can be tested in order to provide support for, or challenge, the theory.
    • also known as Teori, Nazariye, 理論
  2. Theory: In mathematical logic, a theory is a set of sentences in a formal language. Usually a deductive system is understood from context. An element of a theory is then called an axiom of the theory, and any sentence that follows from the axioms is called a theorem of the theory. Every axiom is also a theorem. A first-order theory is a set of first-order sentences.
  3. Theory is a field of study.

Phrases with Theory

Phrases starting with the word Theory:

  1. Theory X
  2. Theory Y

Phrases ending with the word Theory:

  1. m-theory
  2. in theory
  3. set theory
  4. bohr theory
  5. cell theory
  6. game theory
  7. germ theory
  8. Knot theory
  9. Ring theory
  10. wave theory
  11. Chaos Theory
  12. field theory
  13. Grand theory
  14. Graph theory
  15. group theory
  16. Morse Theory
  17. Music theory
  18. Queer theory

View more phrases with the word Theory in thesaurus!

Printed dictionaries and other books with definitions for Theory

Click on a title to look inside that book (if available):

Google previewThe Bedside Baccalaureate (2009)

The second semester by David Rubel

GAME THEORY IS a systematic way of thinking about the possibilities for conflict and cooperation in everyday life. It analyzes...

Google previewGeneralised Algebraic Models (2004)

by Claudia Centazzo

An algebraic theory is a concrete mathematical object - the concept - namely a set of variables together with formal symbols and equalities between these terms. Stated otherwise, an algebraic theory is a small category with finite products.

Google previewGeneral Systems Theory and Psychiatry (1969)

by William Gray, Frederick J. Duhl, Nicholas D. Rizzo

GENERAL SYSTEMS THEORY is a bold new development in human thought which has brought into the range of the scientific approach a great number of complex fields previously unapproachable through classic science. It is an ...

Google previewEverything (2006)

by Robert T. Wood

Steady state is the theory that the universe maintains its basic appearance over time, even though it is expanding. The big bang theory is that at the beginning all existing energy/matter of the universe was condensed and exploded in one “big ...

Google previewA First Course in Noncommutative Rings (2001)

by Tsi-Yuen Lam

Today, ring theory is a fertile meeting ground for group theory (group rings), representation theory (modules), functional...

Google previewThe Responsive Universe (2012)

Meditations and Daily Life Practices by John C. Bader

String Theory is an active research framework in particle physics that attempts to reconcile quantum mechanics and general relativity,

Google previewApplied Social Psychology (2017)

by Linda Steg, Kees Keizer, Abraham P. Buunk, Talib Rothengatter

A • theory is an organized set of principles that describes, explains, and predicts observed events. An example is cognitive dissonance theory, described later in this chapter. • Principles describe a specific process, and they are often integrated ...

Google previewKey Concepts in Public Health (2008)

by Frances Wilson, Andi Mabhala

DEFINITION A theory is the articulation of the framework of beliefs and knowledge which enable us to explain a specific phenomenon. One of the major problems for public health practitioners is that theories are not articulated in everyday ...

Google previewAdministrative Theories And Management Thought 2Nd Ed. (2008)

by R. K. Sapru

Introduction The Principal-Agent Theory is the antimatter to post-modern approaches. It emerged during the 1970s and has served as a mechanism for examining conflict-of-interest-generated problems in aligning the choices of principals ...

Google previewAdvances in the Theory of the Lexicon (2006)

by Dieter Wunderlich

theory. of. Lexical. Event. Structures. and. its. cognitive. motivation. Stefan. Engelberg. 1. Introduction The rise of event semantics in many domains of formal semantics like tense, aspect, quantification, adverbial modification, etc. has had an ...

Google previewEncyclopedia of Communication Theory (2009)

by Stephen W. Littlejohn, Karen A. Foss

Practical Theory Cognitive Theories Indian Rasa ...

Google previewThe Anthem Dictionary of Literary Terms and Theory (2010)

by Peter Auger

CLASSICAL RHETORICAL THEORY drew a distinction between FIGURES that created effects by altering the meanings of words (TROPES, or 'figures of thought' ) or patterning them (SCHEMES, or 'figures of speech'). There is no firm ...

Google previewEncyclopedia of Contemporary Literary Theory (1993)

Approaches, Scholars, Terms by Irene Rima Makaryk

Anglo-American feminist criticism: see Feminist criticism, Anglo-American Archetypal criticism, 3 Black criticism, 5 Chicago School: see Neo- Aristotelian or Chicago School Communication theory, 1 1 Constance School of Reception Aesthetics ...

Google previewAdvances in Generative Lexicon Theory (2012)

by James Pustejovsky, Pierrette Bouillon, Hitoshi Isahara, Kyoko Kanzaki, Chungmin Lee

notion of composition is needed, which is not what one finds in the standard theory of compositionality exemplified in classical Montague Grammar ( Montague 1973). We believe. 1This work forms the basis for more extensive discussion of ...

Google previewEncyclopedia of Feminist Literary Theory (2009)

by Elizabeth Kowaleski-Wallace

Feminist Theory and Legal Strategy. Cambridge, Mass.: Blackwell, 1993. MacKinnon, Catharine. Feminism Unmodified: Discourses on Life and Law. Cambridge: ...

Google previewCritical Dictionary of Film and Television Theory (2005)

by Roberta Pearson, Philip Simpson

Schema theory argues that anindividual's memoryfor people and events is organized according tosystematic models based onthe individual'ssocial andpersonal experiences, which are builtupovertime. Young children, for example, maylack ...

Google previewEncyclopedia of Social Theory (2012)

by Austin Harrington, Barbara L. Marshall, Hans-Peter Müller

ACTION Austin Harrington ACTOR–NETWORK THEORY Andrew Barry ADORNO, THEODOR WIESENGRUND Brian O'Connor AGE Stephen Katz AGENCY David Jary ALEXANDER, JEFFREY C. Bernhard Giesen and Daniel Sˇuber ...

Google previewDictionary of Literary Terms and Literary Theory (2012)

by J. A. Cuddon

Literary theory during and after the Romantic period (q.v.) regarded imitation in sense (b) as a somewhat inferior practice, derivative, lacking in originality. Prior to that and for many centuries (especially during the 18th) it had been regarded as ...

Online dictionaries and encyclopedias with entries for Theory

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Photos about Theory

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View more pictures about Game theory, Chaos Theory, Limit Theory, and Magic Bullet Theory.

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Small photo of Human future uncertainty. Theory of evolution concept, with falling sand taking the shape of a monkey and a man inside a hourglass.Small photo of Istanbul, Turkey, 14 May 2018: Albert Einstein wax figure at Madame Tussauds museum in Istanbul. Albert Einstein was a physicist who developed the general theory of relativity.Small photo of Istanbul, Turkey, 14 May 2018: Albert Einstein wax figure at Madame Tussauds museum in Istanbul. Albert Einstein was a physicist who developed the general theory of relativity.Small photo of Conspiracy theory concept. All Seeing Eye and Pyramid on USA dollar banknote, macro photoSmall photo of ISRAEL - CIRCA 1968: Albert Einstein portrait on Israel 5 pounds banknote close up. Theoretical physicist, general theory of relativity author, Nobel Prize winner.Small photo of ISTANBUL, TURKEY - MARCH 16, 2017: Albert Einstein wax figure at Madame Tussauds museum in Istanbul. Albert Einstein was a physicist who developed the general theory of relativity.Small photo of Twelve spoons on the view. Metaphor for the spoon theory. Theory ask how much energy is available for activities of daily living. The method is use mental, autoimmune, chronic and neurology diseases More...

Video language resources about Theory

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View more videos about In theory, Bang Theory, Ring theory, Field theory, Graph theory, Group theory, Music theory, Queer theory, X-bar theory, Atomic theory, Galois theory, Number theory, Quantum Theory, Rimland Theory, Grounded theory, Political Theory, Information theory, and Theory of knowledge.

See also the pronunciation examples of Theory!

Quotes about Theory

I believe without exception that theory follows practice. Whenever there is a conflict between theory and practice, theory is wrong. As far as I'm concerned, we make theories for what people have done. (David Baker)
more quotes about theory...

Scrabble value of T1H4E1O1R1Y4

The value of this 6-letter word is 12 points. It is included in the first and second editions of the Official Scrabble Players Dictionary.

Anagrams of THEORY

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