conspiracy theory


plural conspiracy theories
: a theory that explains an event or set of circumstances as the result of a secret plot by usually powerful conspirators
the conspiracy theories surrounding Kennedy's assassination
also : a theory asserting that a secret of great importance is being kept from the public
… is best known for … his conspiracy theory that a secret cabal of reptilian humanoids is running the world. Simon Little
… has often been criticized for promoting conspiracy theories such as "birtherism," the theory that President Obama was not born in the U.S. Grace Segers

Examples of conspiracy theory in a Sentence

Conspiracy theories sprung up soon after the leader's assassination.
Recent Examples on the Web When 38-year-old Robert Rauschenberg was named grand prize winner at the esteemed art festival, a furor erupted — and the conspiracy theories took flight. Jessica Gelt, Los Angeles Times, 25 May 2024 State Farm Arena quickly became the subject of conspiracy theories about illicit votes spread by Trump and his associates on social media in the hours following the election. Sudiksha Kochi, USA TODAY, 21 May 2024 But Slovakia’s politics are particularly poisonous, swamped by wild conspiracy theories and bile. Andrew Higgins, New York Times, 19 May 2024 Giuliani filed for bankruptcy after being ordered to pay $148 million to two former election workers for spreading a false conspiracy theory about their role in the 2020 election. CBS News, 18 May 2024 See all Example Sentences for conspiracy theory 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'conspiracy theory.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1863, in the meaning defined above

Time Traveler
The first known use of conspiracy theory was in 1863

Dictionary Entries Near conspiracy theory

Cite this Entry

“Conspiracy theory.” Dictionary, Merriam-Webster, Accessed 13 Jun. 2024.

Kids Definition

conspiracy theory

: a theory that explains an event or situation as being the result of a secret plot
conspiracy theorist noun
Last Updated: - Updated example sentences
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