(ie. duo/double trito-god)
A demigod (ie. partial god) that's two thirds god and one third mortal, (but possibly two thirds the godliness of a typical demigod.
A dual terza-god can have both a god and demigod as a parent).
e.g: 'In the book,' City of the Plague' by Rick Riordan, the Mesopotamian demigod, Gilgamesh is a dual terza-god: He is two-thirds god and one third mortal.'
(Please read my definition of terza-god for more information).