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 site, frequented by far-right supporters of the president, has been used to spread conspiracy theories.
—Neil Vigdor, New York Times, 28 May 2025
Oklahoma will require schools to teach President Trump's 2020 election conspiracy theories.
—Taylor Wilson, USA Today, 23 May 2025
This is a man who has entertained conspiracy theories on a prodigious range of topics: vaccines, fluoride, 5G networks, assassinations, 9/11, election theft.
—Daniel Immerwahr, New Yorker, 23 May 2025
Contrary to conspiracy theories, the Earth’s core isn’t hollow.
—Andrew Paul, Popular Science, 22 May 2025
See All Example Sentences for conspiracy theory
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Neil Vigdor, New York Times, 28 May 2025
Oklahoma will require schools to teach President Trump's 2020 election conspiracy theories.
—Taylor Wilson, USA Today, 23 May 2025
This is a man who has entertained conspiracy theories on a prodigious range of topics: vaccines, fluoride, 5G networks, assassinations, 9/11, election theft.
—Daniel Immerwahr, New Yorker, 23 May 2025
Contrary to conspiracy theories, the Earth’s core isn’t hollow.
—Andrew Paul, Popular Science, 22 May 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 3 Jun. 2025.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share