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.

Round-number theory has also come into play at the key $100 level, which previously acted as support last June, December, and again in January.

From Barron's • May 26, 2026

In theory, it measures how genuinely strong a team's attacking and defensive performance was.

From BBC • May 26, 2026

Monetary policy does not depend only on one theory of growth and inflation.

From MarketWatch • May 22, 2026

Yet there is no observational evidence for macroscopic wormholes, nor any compelling theoretical reason to expect them within Einstein’s theory.

From Science Daily • May 22, 2026

Then he’d explained his theory about how someone—the janitor?

From "Found" by Margaret Peterson Haddix

Vocabulary lists containing theory

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