Webster's Revised Unabridged Dictionary · 1913

disestablishmentarianism

disestablishmentarianism , noun

The doctrine or political position that advocates abrogating the establishment of a church as the official state religion.
Prior to the Puritans, very few earlier believers contended for any form of disestablishmentarianism. — David. W. Hall (Savior or Servant? Putting Government in Its Place: The Covenant Foundation, 1996)