the fixed year of the ancient Egyptians, determined by the heliacal rising of Sirius, and equivalent to 365 days.
Origin of Sothic year
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the fixed year of the ancient Egyptians, 365 days 6 hours long, beginning with the appearance of the star Sirius on the eastern horizon at dawn, which heralded the yearly flooding of the Nile. A Sothic cycle contained 1460 such years
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