Word Study
ogdoad
CIDE DICTIONARY
ogdoad, n. [Gr. 'ogdoa`s, 'ogdoa`dos, from 'oktw` eight.].
A thing made up of eight parts. Milman. [1913 Webster]
OXFORD DICTIONARY
ogdoad, n. a group of eight.
Etymology
LL ogdoas ogdoad- f. Gk ogdoas -ados f. ogdoos eighth f. okto eight
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