conspiracy theory
Pronunciation:
/- θiːəɹiː//- θiːɘɹiː//- θiːəɹi//- θɪɹi/noun
Definitions
A hypothesis alleging that the members of a coordinated group are, and/or were, secretly working together to commit illegal or wrongful actions including attempting to hide the existence of the group and its activities. In notable cases the hypothesis contradicts the mainstream explanation for historical or current events.
(dismissive) Hypothetical speculation that is commonly considered untrue or outlandish.