1. collusion, sedition. 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.