That's a conspiracy theory:

   The term "conspiracy theory" is itself the subject of a conspiracy theory, which posits that the term was popularized by the CIA in order to discredit conspiratorial believers, particularly critics of the Warren Commission, by making them a target of ridicule.

[..]

    The idea that the CIA was responsible for popularising the term "conspiracy theory" was analyzed by Michael Butter, a Professor of American Literary and Cultural History at the University of Tübingen. 

.. and that analysis concluded "yeah, nuh".

https://en.wikipedia.org/wiki/Conspiracy_theory#Origin_and_u...