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.

In these years, Günter dissents from his teacher’s theory of the death drive by arguing that even suicidal struggles are evidence of a desire to go on living.

From The Wall Street Journal • Jun. 3, 2026

The lack of upheaval supports the theory England had their best players in Australia, they just got the approach all wrong.

From BBC • Jun. 3, 2026

To test the theory, Fang and Si conducted laboratory experiments using a thin layer of water driven by electromagnetic forces.

From Science Daily • Jun. 3, 2026

A reformed set of spending rules kicked into force in 2024, and in theory member states risk fines for violations, though the EU has never gone so far.

From Barron's • Jun. 3, 2026

“How about all the stuff Angela told us about the plane and the babies? And—her theory about you two being from the future?”

From "Found" by Margaret Peterson Haddix

Vocabulary lists containing theory

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