Syzygy, or Co-partner, or Complement, of the Ineffable http://altreligion.about.com/library/texts/bl_chaldean.htm
In Gnosticism, a syzygy is a divine active-passive, male-female pair of aeons, complementary to one another rather than oppositional; in their totality they comprise the divine realm of the Pleroma, and in themselves characterise aspects of the Gnostic (known) God. The term is most common in Valentinianism. In some gnostic schools, the counterpart to Christ was Sophia.