ETYM Old Eng. heresie, eresie, Old Fren. heresie, iresie, French hérésie, Latin haeresis, Greek hairein to take, to choose a sect.
A belief that rejects the orthodox tenets of a religion; SYN. unorthodoxy.
Unorthodox religious belief. heretic).
Any doctrine opposed to orthodox belief, especially in religion. Those holding ideas considered heretical by the Christian church have included Gnostics, Arians, Pelagians, Montanists, Albigenses, Waldenses, Lollards, and Anabaptists.