A dissenter (from the Latin , 'to disagree') is one who dissents (disagrees) in matters of opinion, belief, etc. Dissent may include political opposition to decrees, ideas or doctrines and it may include opposition to those things or the fiat of a government, political party or religion.
Usage in Christianity
Dissent from the Anglican Church
thumb|upright=1.15|right|A Catalogue of the Severall Sects and Opinions in England and other Nations: With a briefe Rehearsall of their false and dangerous Tenents, a propaganda [[broadsheet denouncing English dissenters from 1647.]]
In the social and religious history of England and Wales, and, by extension, Ireland, however, it refers particularly to a member of a religious body who has, for one reason or another, separated from the established church or any other kind of Protestant who refuses to recognise the supremacy of the established church in areas where the established church is or was Anglican.
Originally, the term included English and Welsh Roman Catholics In this connotation, the terms dissenter and dissenting, which had acquired a somewhat contemptuous flavor, have tended since the middle of the 18th century to be replaced by nonconformist, a term which did not originally imply secession, but only refusal to conform in certain particulars (for example the wearing of the surplice), with the authorized usages of the established church.