theory

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Contents 1 English 1.1 Etymology 1.2 Pronunciation 1.3 Noun 1.3.1 Derived terms 1.3.2 Related terms 1.3.3 Translations 1.4 See also

[edit] English

[edit] Etymology

English since 1613, from French théorie < Latin theoria < Greek θεωρία ("contemplation, speculation, a looking at, things looked at") < θεωρέω (to look at, view, consider, examine) < θεωρός (spectator) < θέα (a view) + ὁράω (to see, to look).

[edit] Pronunciation

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  Rhymes: -ɪəri

[edit] Noun

theory (countable and uncountable; plural theories)

1. (countable) An unproven conjecture.

   I have a theory about who broke into the school last night, but I have no proof to back it up.

2. (uncountable) An expectation of what should happen, barring unforeseen circumstances.

   So we’ll be there in three hours? — That’s the theory.

3. (countable) (sciences) A coherent statement or set of statements that attempts to explain observed phenomena.

   There is now a well-developed theory of electrical charge.

4. (countable) (sciences) A logical structure that enables one to deduce the possible results of every experiment that falls within its purview.

   The theory of relativity was proposed by Einstein.

5. (uncountable) (mathematics) A field of study attempting to exhaustively describe a particular class of constructs.

   Knot theory classifies the mappings of a circle into 3-space.

6. (countable) (logic) A set of axioms together with all statements derivable from them.

   A theory is consistent if it has a model.

[edit] Derived terms

[edit] Related terms

• theorem
• theoretical
• theorise, theorize

[edit] Translations

[edit] See also

• axiom
• postulate
• proposition