antidisestablishmentarianism (n.)

"opposition to disestablishment of the Church of England," 1838, said by Weekley to be first recorded in Gladstone's "Church and State." The establishment is "the ecclesiastical system established by law" (1731), specifically "the Church of England" (1731). Hence establishmentarianism "the principle of a state church" (1846) and disestablishment "act of withdrawing (a church) from a privileged relation to the state" (1747; see disestablish), which are married in this word. Rarely used at all now except in examples of the longest words, among which it has been counted at least since 1901.