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
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
Grace Segers Examples of conspiracy theory in a Sentence
Conspiracy theories sprung up soon after the leader's assassination.
Recent Examples on the Web
That’s a novel concept for a franchise dogged by injuries and an electrical substation conspiracy theories.
—Cam Inman, Mercury News, 27 May 2026
One of the clearest examples of an anti-feminist conspiracy theory that lay behind a neo-Nazi attack, DiBranco said, took place in Norway in 2011.
—Odette Yousef, NPR, 27 May 2026
The judge also learned from New Haven State’s Attorney John Doyle that Boyne violated a confidentiality order from Brown by providing a statement Moukawsher gave to the state probation department to another blogger who promotes Boyne and his conspiracy theories.
—Edmund H. Mahony, Hartford Courant, 26 May 2026
The wise audience on the platform, too, did not float any conspiracy theories and even directed the user to the likely cause of this superachievement, as identified by the panels.
—Ameya Paleja, Interesting Engineering, 25 May 2026
See All Example Sentences for conspiracy theory
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Cam Inman, Mercury News, 27 May 2026
One of the clearest examples of an anti-feminist conspiracy theory that lay behind a neo-Nazi attack, DiBranco said, took place in Norway in 2011.
—Odette Yousef, NPR, 27 May 2026
The judge also learned from New Haven State’s Attorney John Doyle that Boyne violated a confidentiality order from Brown by providing a statement Moukawsher gave to the state probation department to another blogger who promotes Boyne and his conspiracy theories.
—Edmund H. Mahony, Hartford Courant, 26 May 2026
The wise audience on the platform, too, did not float any conspiracy theories and even directed the user to the likely cause of this superachievement, as identified by the panels.
—Ameya Paleja, Interesting Engineering, 25 May 2026
See All Example Sentences for conspiracy theory
Cite this Entry
“Conspiracy theory.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/conspiracy%20theory. Accessed 3 Jun. 2026.
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