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

That is the same theory underpinning the controversial airstrikes since September on alleged drug traffickers' boats in the Caribbean and the Pacific.

From Barron's • May 29, 2026

Brian will have to pay filing costs and, if the judge did find that he took a frivolous case, he could, in theory, be held liable for Adam’s legal fees, too.

From MarketWatch • May 28, 2026

Knox and the others knew, in theory, what Enigma looked like.

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin

Vocabulary lists containing theory

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