zurvanism: a heretical Zoroastrian doctrine holding that Zurvan was the ultimate source of the universe and that both Ahura Mazda and Ahriman were Zurvan's offspring
theological doctrine: the doctrine of a religious group
significant digit: any digit of a number that is known with certainty; any digit of a number beginning with the leftmost non-zero digit and ending with the rightmost non-zero digit (or a zero considered to be the exact value)