conspiracy theory

American  

[kuhn-spir-uh-see theer-ee] / kənˈspɪr ə si ˌθɪər i /

noun

1. a theory that rejects the standard explanation for an event and instead credits a covert group or organization with carrying out a secret plot.

   One popular conspiracy theory accuses environmentalists of sabotage in last year's mine collapse.

2. a belief that a particular unexplained event was caused by such a covert group.

   A number of conspiracy theories have already emerged, purporting to explain last week's disappearance of a commercial flight over international waters.

3. the idea that many important political events or economic and social trends are the products of deceptive plots that are largely unknown to the general public.

   The more I learn about the activities of intelligence agencies, the less far-fetched I find many geopolitical conspiracy theories.

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conspiracy theory British  

noun

1. the belief that the government or a covert organization is responsible for an event that is unusual or unexplained, esp when any such involvement is denied

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Usage

What does conspiracy theory mean? A conspiracy theory is an explanation of an event that claims it was the result of a secret and often complex and evil plot by multiple people.Conspiracy theories and the conspiracy theorists who promote or formulate them often reject the standard or accepted explanation of unexplained or unusual events and claim that they are the doing of evil conspirators secretly conspiring behind the scenes.Conspiracy most commonly means a secret plan by multiple people to do something evil or illegal. Conspiracy can also refer to the act of making such plans—the act of conspiring—or to the group making the plans. The people involved can be called conspirators.In conspiracy theory, the word theory is used in a general way to refer to a proposed explanation that has not been proven. But conspiracy theorists don’t usually treat such theories as just guesses—they often promote them as fact, no matter how bizarre or far-fetched they may be.Most conspiracy theories involve supposedly secret knowledge of the supposedly secret and evil dealings of powerful people, especially politicians, government officials, billionaires, and celebrities. Such plots are often claimed to have the goal of controlling world events and ordinary people.Example: Why are several supposedly legitimate news outlets promoting conspiracy theories that have been repeatedly debunked?

Other Word Forms

• conspiracy theorist noun

Etymology

Origin of conspiracy theory

First recorded in 1905-10

Example Sentences

And this is always … again, I come back to the conspiratorial point because I do think that that is a form of conspiracy theory.

From The Wall Street Journal • Feb. 5, 2026

He has never shared a conspiracy theory or shared anger at a group or been unpatriotic.

From Slate • Jan. 26, 2026

They face competition from conspiracy theory drama Bugonia, a new screen adaptation of Frankenstein, Hollywood satire Jay Kelly and music biopic Springsteen: Deliver Me from Nowhere.

From BBC • Dec. 7, 2025

Misinformation, conspiracy theory and disinformation spread like mold in a flooded house, permeating so many discussions.

From Salon • Nov. 22, 2025

Lynn rolls her eyes, and he hurries on, probably to avoid hearing Lynns Divergent conspiracy theory again.

From "Insurgent" by Veronica Roth