Ogdoad may refer to:
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Ogdoad (Egyptian)
In Egyptian mythology, the Ogdoad ( "the Eightfold"; , a plural nisba of "eight") were eight primordial deities worshiped in Hermopolis.
The earliest certain reference to the Ogdoad is from the Eighteenth Dynasty, in a dedicatory inscripti ...
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Ogdoad (Gnosticism)
The concept of an Ogdoad (Greek language, Greek: ὀγδοάς) appears in Gnosticism, Gnostic systems of the early Christian era, and was further developed by the theologian Valentinus (Gnostic), Valentinus (''ca''. 160 AD).
The 8, number eight ...
See also
*''Ogdoades'', a work of history by
Guillaume du Bellay
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Tonality diamond
In music theory and musical tuning, tuning, a tonality diamond is a two-dimensional diagram of ratios in which one dimension is called the Otonality and Utonality, otonality and the other is called the utonality.Rasch, Rudolph (2000). "A Word or ...
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