theory

[thee-uh-ree, theer-ee] / ˈθi ə ri, ˈθɪər i /

NOUN

hypothesis, belief

Synonyms

STRONGEST

approach argument assumption code concept doctrine idea ideology method philosophy plan position premise proposal provision rationale scheme speculation suspicion system thesis understanding

STRONG

base basis codification conditions conjecture dogma feeling foundation grounds guess guesswork hunch impression outlook postulate presentiment presumption shot stab supposal supposition surmise theorem

WEAK

formularization suppose systemization

Antonyms

STRONGEST

disbelief fact information reality truth

STRONG

calculation knowledge measurement proof

WEAK

certainty

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Though aimed at fans, there is in theory nothing stopping an opposition member of staff from turning up and recording observations.

From BBC • Jun. 3, 2026

To test the theory, Fang and Si conducted laboratory experiments using a thin layer of water driven by electromagnetic forces.

From Science Daily • Jun. 3, 2026

A reformed set of spending rules kicked into force in 2024, and in theory member states risk fines for violations, though the EU has never gone so far.

From Barron's • Jun. 3, 2026

Neoclassical economic theory assumes how this rational individual behaves in response to prices and incentives, and this forms a basis to model the economy.

From The Wall Street Journal • Jun. 2, 2026

Unlike the larger earthquakes, where scientists had a single, generally accepted theory about what was happening far below the surface, there were several theories about what caused harmonic tremors.

From "Mountain of Fire" by Rebecca E. F. Barone

Vocabulary lists containing theory

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