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.

State wildlife officials have finally come up with a theory to explain where a giant, highly destructive rodent that’s been terrorizing California came from: Oregon.

From Los Angeles Times • Apr. 10, 2026

They have not yet been directly observed, but they are predicted by theory.

From Science Daily • Apr. 8, 2026

Looking at AAL’s monthly chart one can see how round number theory has come into play at the $10 figure:

From Barron's • Apr. 8, 2026

Supporters love the "madman theory" for its ability to keep opponents off guard and pull off previously unthinkable achievements.

From BBC • Apr. 8, 2026

Tonight was the vote on Amendment S in Ravenskill, and if Seven’s theory was correct, there would be another string of cuco attacks—making this the perfect time for the Witchlings to strike.

From "Witchlings" by Claribel A. Ortega

Vocabulary lists containing theory

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