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

Close friends will, in theory, congratulate you on your achievements.

From MarketWatch • May 26, 2026

Although the new theory cannot be directly tested in distant cosmic environments, earlier laboratory experiments appear to support the findings.

From Science Daily • May 26, 2026

“Now I shall put my theory to the test,” she thought.

From "The Long-Lost Home" by Maryrose Wood

Vocabulary lists containing theory

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