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English definition of “theory”

theory

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