hebdomad

noun

1. (obsolete)A group of seven.

   “Let us now pass to the other species of the hebdomad, which is comprehended in the decad, and which exhibits an admirable nature no less than the former hebdomad. This, therefore, is composed of one, two, and four, which possess two most harmonic ratios, the duple and the quadruple; the former of which forms the symphony diapason, and the latter the symphony desdiapason.”

   “From the seventh of Artaxerxes to the death of Christ, are exactly seventy hebdomads complete. From the same epoch to the commencement of John's ministry, are exactly sixty-nine hebdomads. [...] From the coming of Christ, that is, from the first preaching of the Gospel, to the destruction of Jerusalem, are seven hebdomads; and this event happened exactly at the end of the first half of the seventh hebdomad, which "sacrifice and oblation" visibly ceased.”

   “The word "hebdomad" stands in the same relation to seven, that "decad" does to ten, or our English word "dozen" to twelve. As therefore we can say a dozen of days, or a dozen of months, or a dozen of years, so we can say, a hebdomad of days, (i.e. seven days,) or a hebdomad of months, (i.e. seven months,) or a hebdomad of years, (i.e. seven years.)”

2. (historical)A period of seven days; a week.

   “For that ſaying of our Saviour, My Father worketh hitherto, and I work, is by the moſt judicious underſtood of the works of preſervation and providence: Thoſe of creation being concluded within the firſt Hebdomade, accordingly as is expreſt in the Hiſtory, that God on the ſeventh day reſted from all his works.”

3. A group of seven world-creating archons (supernatural beings) often regarded as somewhat hostile; also, a term of address for the Demiurge (“a being sometimes seen as the creator of evil”).

   “When, then, the Great Archon had been orally instructed, and every creature of the Ogdoad had been orally instructed and taught, and [after] the mystery became known to the celestial [powers], it was also necessary that afterwards the Gospel should come to the Hebdomad, in order likewise that the Archon of the Hebdomad might be similarly instructed and indoctrinated into the Gospel.”

   “The light came down from the Hebdomad upon Jesus the Son of Mary. That this descent of the light was represented as taking place at the Annunciation, and not merely at the Baptism, is clearly implied in the express reference to the words of the angel in Luke i. 35, "A Holy Spirit shall come upon thee," [...]”