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 has caused a rift between President Donald Trump and his MAGA base, who have long promoted conspiracy theories tied to Epstein and his 2019 death behind bars.
—Solcyré Burga, Time, 14 July 2025
When your worldview is based on a conspiracy theory, anything that doesn’t align with that theory becomes another conspiracy.
—Bill Goodykoontz, AZCentral.com, 14 July 2025
Reports showed far-right supporters spreading conspiracy theories accusing Biden of complicity contributing to a spike in political threats and violence in late 2024.
—Theo Burman, MSNBC Newsweek, 13 July 2025
The release was intended to address conspiracy theories about Epstein’s apparent suicide in federal custody.
—Dhruv Mehrotra, Wired News, 11 July 2025
See All Example Sentences for conspiracy theory
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Solcyré Burga, Time, 14 July 2025
When your worldview is based on a conspiracy theory, anything that doesn’t align with that theory becomes another conspiracy.
—Bill Goodykoontz, AZCentral.com, 14 July 2025
Reports showed far-right supporters spreading conspiracy theories accusing Biden of complicity contributing to a spike in political threats and violence in late 2024.
—Theo Burman, MSNBC Newsweek, 13 July 2025
The release was intended to address conspiracy theories about Epstein’s apparent suicide in federal custody.
—Dhruv Mehrotra, Wired News, 11 July 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 20 Jul. 2025.
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