2. Conspiracy,plot,intrigue,cabal all refer to surreptitious or covert schemes to accomplish some end, most often an evil one. A conspiracy usually involves a group entering into a secret agreement to achieve some illicit or harmful objective: a vicious conspiracy to control prices. A plot is a carefully planned secret scheme, usually by a small number of persons, to secure sinister ends: a plot to seize control of a company. An intrigue usually involves duplicity and deceit aimed at achieving either personal advantage or criminal or treasonous objectives: the petty intrigues of civil servants.Cabal refers either to a plan by a small group of highly-placed persons to overthrow or control a government, or to the group of persons themselves: a cabal of powerful lawmakers.
mid-14c., from Anglo-French conspiracie, Old French conspiracie "conspiracy, plot," from Latin conspirationem (nominative conspiratio) "agreement, union, unanimity," noun of action from conspirare (see conspire); earlier in same sense was conspiration (early 14c.), from French conspiration (13c.), from Latin conspirationem. An Old English word for it was facengecwis. As a term in law, from 1863. Conspiracy theory is from 1909.