Platonic year

American  

noun

Astronomy.

1. a period of about 26,000 years, equal to the time required for a complete revolution of the equinoxes.

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Etymology

Origin of Platonic year

First recorded in 1630–40

Example Sentences

There is a figure of the great Platonic year with a phenix on his hand on the reverse of a medal of Adrian.

From The Botanic Garden A Poem in Two Parts. Part 1: the Economy of Vegetation by Darwin, Erasmus

Oh for the revolution of the great Platonic year, that those times might come over again!

From Table Talk Essays on Men and Manners by Hazlitt, William