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
His death has ignited conspiracy theories, calls for gun control, and a nationwide political debate over his legacy.
—Lily Mae Lazarus, Fortune, 20 Sep. 2025
Patel, a podcaster who once called for the release of the files and helped propagate conspiracy theories about why they weren’t being made public, testified just days before Acosta is set to finally tell his side of the story before a congressional committee.
—Julie K. Brown, Miami Herald, 18 Sep. 2025
The French first couple's lawyer, Tom Clare, recently spoke with BBC about how the conspiracy theory had affected Emmanuel, 47, and Brigitte, 72, and explained how the couple plans to disprove the claims once and for all.
—Meredith Kile, PEOPLE, 18 Sep. 2025
The kind of free speech and lively discourse that Kirk espoused involved spreading hateful conspiracy theories and misinformation.
—Kyle Chayka, New Yorker, 17 Sep. 2025
See All Example Sentences for conspiracy theory
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Lily Mae Lazarus, Fortune, 20 Sep. 2025
Patel, a podcaster who once called for the release of the files and helped propagate conspiracy theories about why they weren’t being made public, testified just days before Acosta is set to finally tell his side of the story before a congressional committee.
—Julie K. Brown, Miami Herald, 18 Sep. 2025
The French first couple's lawyer, Tom Clare, recently spoke with BBC about how the conspiracy theory had affected Emmanuel, 47, and Brigitte, 72, and explained how the couple plans to disprove the claims once and for all.
—Meredith Kile, PEOPLE, 18 Sep. 2025
The kind of free speech and lively discourse that Kirk espoused involved spreading hateful conspiracy theories and misinformation.
—Kyle Chayka, New Yorker, 17 Sep. 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 22 Sep. 2025.
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