What does "heretic" mean?

Heretic: 2. (R. C. Ch.) One who having made a profession of Christian belief, deliberately and pertinaciously refuses to believe one or more of the articles of faith "determined by the authority of the universal church." Addis & Arnold. A heretic is one whose errors are doctrinal, and usually of a malignant character, tending to subvert the true faith. A schismatic is one who creates a schism, or division in the church, on points of faith, discipline, practice, etc., usually for the sake of personal aggrandizement. A sectarian is one who originates or is an ardent adherent and advocate of a sect, or distinct organization, which separates from the main body of believers.

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