ogdoad Meaning, Definition & Usage

  1. noun the cardinal number that is the sum of seven and one
    octet; octad; eight; VIII; eighter; 8; eighter from Decatur; octonary.

WordNet

Og"do*ad noun
Etymology
Gr. , , from eight.
Definitions
  1. A thing made up of eight parts. Milman.

Webster 1913