Sethian adjective 2noun 1forms 3 adjective2 •Of or relating to the Egyptian god SetBut if these hippopotami are Sethian, how could Apophis, a professed follower of Seth, allow this to go on in his own city of Avaris? — 1960 •Of or relating to the Sethians noun1 •A member of an ancient Christian Gnostic sect who venerated the Biblical Seth, third son of Adam and Eve, depicted in their creation myths as a divine incarnation. formsSethians · more Sethian · most Sethian