i got that from Wiki.....
History[edit]
According to the Oxford English Dictionary, the first use of the phrase "conspiracy theory" occurred in a 1909 article in The American Historical Review.[15][16] Other sources predate this use by nearly four decades to at least 1871, where it is used in The Journal of Mental Science reporting on a conference of the Fifth Quarterly Meeting of the Medico-Psychological Association (now the Royal College of Psychiatrists), held on January 27, 1870:
Acquired derogatory meaning[edit]
Originally a neutral term, since the mid-1960s it has acquired a somewhat derogatory meaning, implying a paranoid tendency to see the influence of some malign covert agency in events.[18] The term is often used to automatically dismiss claims that the critic deems ridiculous, misconceived, paranoid, unfounded, outlandish, or irrational.[19] A conspiracy theory that is proven to be correct, such as the notion that United States President Richard Nixon and his aides conspired to cover up Watergate, is usually referred to as something else, such as investigative journalism or historical analysis.[20] Despite conspiracy theorists often being dismissed as a "fringe group," evidence suggests that people from "a broad cross-section of Americans today — traversing ethnic, gender, education, occupation, and other divides" believe in a wide variety of conspiracy theories.[21]
Term of ridicule[edit]
Assessing the prevalent use of the term to ridicule or dismiss, Professor Rebecca Moore observes, "The word 'conspiracy' works much the same way the word 'cult' does to discredit advocates of a certain view or persuasion. Historians do not use the word 'conspiracy' to describe accurate historical reports. On the contrary, they use it to indicate a lack of veracity and objectivity."[22]
http://en.wikipedia.org/wiki/Conspiracy_theory
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