A cabal is a number of persons united in some close design, usually to promote their private views and interests in church or state by intrigue; a secret association composed of a few designing persons; a junto. The term can also be used to refer to the designs of such persons. It derives from Kabbalah (which has numerous spelling variations), the mystical interpretation of the Hebrew scripture, and originally meant either an occult doctrine or a secret.
The term took on its present invidious meaning from a group of five ministers chosen in 1667 by King Charles II (Clifford, Arlington, Buckingham, Ashley Cooper [later earl of Shaftesbury], and Lauderdale), whose initial letters coincidentally spelled Cabal. This Cabal, never very unified in its members' aims and sympathies, fell apart by 1672; Shaftesbury even became one of Charles II's fiercest opponents. The term, however, continued to hold its general meaning of intrigue and conspiracy. Its usage still carries strong connotations of shadowy corners and occult influence; a cabal is more evil and selective than, say, a faction, which is simply selfish.
During the rise of Usenet, the term gained great coinage as a semi-ironic description of the efforts of people to maintain some order over the chaotic, anarchic Usenet community; see backbone cabal, There is no Cabal. As in this specific case, references to an alleged cabal often fall within the realm of the conspiracy theory.