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.

The conspiracy theory grouped together several so-called "missing scientists" including a retired Air Force general, an engineer, and a custodian.

From BBC • Jun. 2, 2026

Rick Rubin once said to me — he has a theory about album track lists where he thinks that the first four songs are totally crucial.

From Los Angeles Times • Jun. 1, 2026

In this case, that meant pulling from both algebraic number theory and discrete geometry, which have about as much in common as the marathon and pole vault.

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

Like this is a crucial piece of evidence in some wild conspiracy theory.

From "The Sea in Winter" by Christine Day

Vocabulary lists containing theory

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