theory Definition in the Cambridge English Dictionary
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Definition of “theory” - English Dictionary

Definition of "theory" - American English Dictionary

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theorynoun [C/U]

 us   /ˈθɪər·i, ˈθi·ə·ri/
something ​suggested as a ​reasonableexplanation for ​facts, a ​condition, or an ​event, esp. a ​systematic or ​scientificexplanation: [U] Adele took a ​course in ​modernpolitical theory. [C] I have a theory (= an ​opinion) about why everybody in the ​city is in such a ​hurry.
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(Definition of theory from the Cambridge Academic Content Dictionary © Cambridge University Press)

Definition of "theory" - British English Dictionary

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theorynoun [C or U]

uk   /ˈθɪə.ri/  us   /ˈθɪr.i/
B2 a ​formalstatement of the ​rules on which a ​subject of ​study is ​based or of ​ideas that are ​suggested to ​explain a ​fact or ​event or, more ​generally, an ​opinion or ​explanation: economic theory scientific theory Darwin's theory ofevolution He has a theory that the ​hole was ​caused by a ​meteorite.in theory B2 If something is ​possible in theory, it should be ​possible, but often it does not ​happen in that way: In theory, the ​journey should take three ​hours, but in ​practice it usually ​takes four because of ​roadworks.
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(Definition of theory from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)

Definition of "theory" - Business English Dictionary

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theorynoun

uk   us   /ˈθɪəri/ (plural theories)
[C or U] a ​formalstatement of ​ideas that are suggested to explain a fact or ​event, or how something ​works: He has four theories to explain ​organizationalchange and ​development.economic/political theory Economic theory says that there is little ​connection between the euro's ​value against the ​dollar or the ​yen and the ​success of ​monetaryunion itself.a theory of sth In this ​article the ​authorsdevelop a theory of high-performing ​organizations.
[C or U] a ​formalstatement of the ​rules or ​principles on which an ​activity or a ​subject of ​study is ​based: management/organization theory This ​casestudy has important implications for ​management theory the theory and ​practice of ​running a ​department
[C] a ​statement of an ​opinion or an explanation of an ​idea that is believed to be ​true, but might be wrong: The theory is that ​staffreact better to praise than to criticism. People will ​buy the ​product if you put it in the ​rightplace - well, that's the theory anyway.
in theory if something is possible in theory, it should be possible, but often it does not ​happen in that way: In theory, you can be up and ​trading in a just a day. Employing fewer ​people sounds great in theory, but how's it going to ​work out in ​practice?
(Definition of theory from the Cambridge Business English Dictionary © Cambridge University Press)
Translations of “theory”
in Korean 이론…
in Arabic نَظَرِيّة…
in Malaysian teori…
in French théorie…
in Russian теория…
in Chinese (Traditional) 理論, 學說, 意見…
in Italian teoria…
in Turkish kuram, teori…
in Polish teoria…
in Spanish teoría…
in Vietnamese lý thuyết, lý luận, nguyên lý…
in Portuguese teoria…
in Thai สมมติฐาน, ทฤษฎี…
in German die Theorie…
in Catalan teoria…
in Japanese 理論, 説…
in Chinese (Simplified) 理论, 学说, 意见…
in Indonesian teori…
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“theory” in Business English

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