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
The memo came after top Trump officials like Attorney General Pam Bondi and FBI Director Kash Patel had long promised the files’ release—and played a role in spreading the conspiracy theories the memo debunked—sparking broad public backlash, including from Trump’s base.
—Alison Durkee, Forbes.com, 19 Aug. 2025
After Donald Trump's 2020 election defeat, a wave of conspiracy theories spread among some of his supporters, alleging widespread voter fraud.
—Gabe Whisnant, MSNBC Newsweek, 18 Aug. 2025
There was no indication that Newsmax will offer any on-air apology or acknowledgment of its false claims about Dominion, a voting hardware and software company that became the target of many pro-Trump conspiracy theories about the 2020 presidential election.
—Brian Stelter, CNN Money, 18 Aug. 2025
But the arrival of Maxwell, whose association with Epstein and the baseless conspiracy theories surrounding his suicide in a New York City jail in 2019, has spurred a whole new level of concern for some residents.
—Suzanne Gamboa, NBC news, 9 Aug. 2025
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Alison Durkee, Forbes.com, 19 Aug. 2025
After Donald Trump's 2020 election defeat, a wave of conspiracy theories spread among some of his supporters, alleging widespread voter fraud.
—Gabe Whisnant, MSNBC Newsweek, 18 Aug. 2025
There was no indication that Newsmax will offer any on-air apology or acknowledgment of its false claims about Dominion, a voting hardware and software company that became the target of many pro-Trump conspiracy theories about the 2020 presidential election.
—Brian Stelter, CNN Money, 18 Aug. 2025
But the arrival of Maxwell, whose association with Epstein and the baseless conspiracy theories surrounding his suicide in a New York City jail in 2019, has spurred a whole new level of concern for some residents.
—Suzanne Gamboa, NBC news, 9 Aug. 2025
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 28 Aug. 2025.
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