Schism

A schism ( , or (less commonly) ) is a division between people, usually belonging to an organization, movement, or religious denomination. The word is most frequently applied to a split in what had previously been a single religious body, such as the Great East–West Schism or the Western Schism. It is also used of a split within a non-religious organization or movement or, more broadly, of a separation between two or more people, be it brothers, friends, lovers, etc.

A schismatic is a legalistic, often pejorative term for person who creates or incites schism in an organization or who is a member of a splinter group. People and groups declared schismatic often reject the label. As an adjective, schismatic means pertaining to a schism or schisms, or to those ideas, policies, etc. that are thought to lead towards or promote schism. While the concept of schism exists across a wide number of faiths, the specific term, implications, and jurisprudence around schism very widely across religions traditions and denominations. In academic scholarship on schisms, a different gloss, or the underlying term untranslated, is sometimes used to reflect distinctions of that religion's conception of schism.

In some religions, such as Buddhism and much of Christianity, the charge of schism is distinguished from that of heresy, since the offence of schism concerns not differences of belief or doctrine but promotion of, or the state of division, especially among groups with differing pastoral jurisdictions and authority. However, schisms frequently involve mutual accusations of heresy. Other faiths view heresy and schism as inexorably linked, and even within a faith this can change depending on context. In Roman Catholicism, every heresy is a schism, though not every schism is a heresy. This is further complicated by mutual charges of heresy between schismatic groups and the institutions they split from, with schismatics often declaring themselves as staying true to a religion's teachings and the main body heretically deviant, as with the 2026 schism between Roman Catholicism and the Society of Saint Pius X. Whether something is schismatic, heretical, or both, is an issue of ideological perception when both groups claim legitimacy.