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.

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

In theory GDP and GDI should be the same, though in practice they differ slightly because of statistical imprecision.

From The Wall Street Journal • May 29, 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

Quantum computers can in theory solve problems which the most powerful conventional computers cannot.

From BBC • May 28, 2026

I held up my finger, ready to poke holes in her theory.

From "Sir Fig Newton and the Science of Persistence" by Sonja Thomas

Vocabulary lists containing theory

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