The Collaborative International Dictionary
Marcionite \Mar"cion*ite\ (m[aum]r"sh[u^]n*[imac]t), n. (Eccl.
Hist)
A follower of Marcion, a Gnostic of the second century, who
adopted the Oriental notion of the two conflicting
principles, and imagined that between them there existed a
third power, neither wholly good nor evil, the Creator of the
world and of man, and the God of the Jewish dispensation.
--Brande & C.
Douglas Harper's Etymology Dictionary
1540, early Christian sect, named for Gnostic Marcion of Sinope (c.140), who denied any connection between the Old Testament and the New. They contrasted the barbaric and incompetent creator in the Old Testament, who favored bandits and killers, with the "higher god" of Christ. They also emphasized virginity and rejection of marriage. They flourished, especially in the East, until late 4c.
Usage examples of "marcionite".
It was sometimes faintly insinuated, and sometimes boldly asserted, that the same bloody sacrifices, and the same incestuous festivals, which were so falsely ascribed to the orthodox believers, were in reality celebrated by the Marcionites, by the Carpocratians, and by several other sects of the Gnostics, who, notwithstanding they might deviate into the paths of heresy, were still actuated by the sentiments of men, and still governed by the precepts of Christianity.
Later Marcionites expressly taught Patripassianism, and have on that account been often grouped with the Sabellians.
It was sometimes faintly insinuated, and sometimes boldly asserted, that the same bloody sacrifices, and the same incestuous festivals, which were so falsely ascribed to the orthodox believers, were in reality celebrated by the Marcionites, by the Carpocratians, and by several other sects of the Gnostics, who, notwithstanding they might deviate into the paths of heresy, were still actuated by the sentiments of men, and still governed by the precepts of Christianity.