conspiracy theory

noun

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 And with it, a number of conspiracy theories like unsubstantiated claims of non-citizen voting. ABC News, 13 Oct. 2024 There’s his erratic online behavior, his promotion of conspiracy theories on X, his far-right-wing dalliances, and his recent decision to go all-in on one side of a divisive presidential election. Dev Patnaik, Forbes, 12 Oct. 2024 The Gateway Pundit, currently being sued over false election claims, has doubled down on conspiracy theories about the presidential election, according to a new analysis. Melissa Cruz, USA TODAY, 12 Oct. 2024 What to watch: By reflexively rejecting expert opinions, some pro-Trump Republicans have left themselves vulnerable to conspiracy theories. Zachary Basu, Axios, 12 Oct. 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.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/conspiracy%20theory. Accessed 31 Oct. 2024.

Kids Definition

conspiracy theory

noun
: 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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