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.

Pedro Pizarro, chief executive of Edison International, later said that a leading theory of the fire’s ignition was that the idle line became energized briefly through induction, sparking the fire.

From Los Angeles Times • Jun. 9, 2026

In this situation, in theory any verdict applies only to Gasly, so even if Alpine won, only his race result would change.

From BBC • Jun. 9, 2026

Living a healthy life is easy in theory but hard in practice.

From The Wall Street Journal • Jun. 7, 2026

In theory, entangled quantum states can detect extremely small differences in magnetic fields or gravitational fields between separate locations.

From Science Daily • Jun. 6, 2026

In the decades after the Mona Lisa theft, this theory would get compressed.

From "The Mona Lisa Vanishes" by Nicholas Day

Vocabulary lists containing theory

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