Wikipedia
Anti-Orthodoxy or Anti-Orthodoxism is negative attitude or hostility towards clergy and adherents of Orthodox Christianity because of their religious beliefs and practices. The term is generally used to describe negativism towards Eastern Orthodox Church and sometimes it is also used to describe same attitude towards Oriental Orthodox Church. Use of the term is not restricted only to attitudes against Orthodox branches of Eastern Christianity and it can also be used to describe negativism against Orthodox Christians of the West.
Orthodox Christians, Eastern or Oriental and Western, have been persecuted throughout history by other Christians, by members of some other Religions and also in modern times by anti-religious political movements and regimes in some countries. Since non-Christian and non-religious oppositions towards Orthodoxy were often motivated by basic animosity towards Christians or religious people in general, the term Anti-Orthodoxy in mainly used to describe internal Christian opposition or hostility of some non-Orthodox Christians towards Christian Orthodoxy.