Why is the ninth month called September?
1520s, "mystical interpretation of the Old Testament," later "society, small group meeting privately" (1660s), from French cabal, in both senses, from Medieval Latin cabbala (see cabbala). Popularized in English 1673 as an acronym for five intriguing ministers of Charles II (Clifford, Arlington, Buckingham, Ashley, and Lauderdale), which gave the word its sinister connotations.
a private organization or party engaged in secret intrigues; also, the intrigues themselves. In England the word was used during the 17th century to describe any secret or extralegal council of the king, especially the foreign committee of the Privy Council. 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.