Dissenter, n.
1. One who dissents; one who differs in opinion, or declares his disagreement.
2. (Eccl.)
One who separates from the service and worship of an established church; especially, one who disputes the authority or tenets of the Church of England; a nonconformist. Dissenters from the establishment of their several countries. Burke. Robert Brown is said to have the first formal dissenter. Shipley.
Note: "The word is commonly applied only to Protestants. The Roman Catholics are generally referred to as a distinct class." Brande & C.
Shades of meaning
Fernald has no entry of its own for dissenter; he lists it under heretic.
Where he writes about it:
Dissenter and non-conformist are terms specifically applied to English subjects who hold themselves aloof from the Church of England; the former term is extended to non-adherents of the established church in some other countries, as Russia. — from heretic
Antonyms
none given