The Collaborative International Dictionary of English v.0.48:

Southcottian \South*cot"ti*an\, n. (Eccl. Hist.)
   A follower of Joanna Southcott (1750-1814), an Englishwoman
   who, professing to have received a miraculous calling,
   preached and prophesied, and committed many impious
   absurdities.
   [1913 Webster]