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 Robinson has ignited intense backlash for his history of comments ranging from support of antisemitic conspiracy theories to lambasting school shooting victims. Mark Robinson, USA TODAY, 17 Mar. 2024 Immediately, calls were made for more information, the speculation went stratospheric, and in the absence of actual news—after a long, dignified silence from the palace—conspiracy theories followed. Elle Turner, Glamour, 15 Mar. 2024 Instead, Kennedy is front-loading two men who the young male voter might find in a late-night TikTok or Instagram scroll and who are known for their own fondness for indulging in conspiracy theories and misinformation. Anna Merlan, WIRED, 14 Mar. 2024 While CrowdTangle is used by news outlets, academic researchers, and regulators to monitor viral content, such as the spread of misinformation and conspiracy theories, Meta Content Library will only be available to nonprofit researchers and academics. Britney Nguyen, Quartz, 14 Mar. 2024 Kate Middleton, the Princess of Wales, has found herself at the center of a web of conspiracy theories about her wellness, whereabouts, and Photoshop capabilities; King Charles was recently diagnosed with cancer; and The Crown stirred up more intrigue than ever about the living royals’ lives. Hannah Jackson, Vogue, 13 Mar. 2024 As the internet spiraled with conspiracy theories, Kate publicly addressed the Photoshop controversy a day later on March 11. Kelsie Gibson, Peoplemag, 12 Mar. 2024 Related article Why the royals have become the center of conspiracy theories Questions about the Mother’s Day image first emerged on social media. Lauren Said-Moorhouse, CNN, 11 Mar. 2024 The Kate Middleton conspiracy theories also started up in conjunction with several other tragic events and unfortunate happenings within the royal family. Sydney Lake, Fortune, 11 Mar. 2024

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 29 Mar. 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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