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.

Another theory is that the weight of opportunity is becoming a burden on those left in the men's draw.

From BBC • May 31, 2026

Now they are solving classic problems in combinatorial geometry using algebraic number theory.

From The Wall Street Journal • May 30, 2026

Yale economist Robert Shiller is widely credited with developing much of the theory behind perpetual futures contracts back in the 1990s.

From MarketWatch • May 29, 2026

Zhang and his colleagues set out to examine a key assumption behind that theory.

From Science Daily • May 29, 2026

In Jim Grant’s essay, Steve Eisman found independent confirmation of his theory of the financial world.

From "The Big Short" by Michael Lewis

Vocabulary lists containing theory

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