priscillianist

from The Century Dictionary.

• noun One of a sect, followers of Priscillian, a Spanish heretic of the fourth century.
• noun A name given to the Montanists (see Montanist), from their alleged prophetess Priscilla.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Eccl. Hist.) A follower of Priscillian, bishop of Avila in Spain, in the fourth century, who mixed various elements of Gnosticism and Manicheism with Christianity.