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eon

or ae·on

[ ee-uhn, ee-on ]
/ ˈi ən, ˈi ɒn /
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noun

an indefinitely long period of time; age.
the largest division of geologic time, comprising two or more eras.
Astronomy. one billion years.

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Origin of eon

see origin at aeon
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for eon

eon
/ (ˈiːən, ˈiːɒn) /

noun

the usual US spelling of aeon
geology the longest division of geological time, comprising two or more eras
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for eon

eon
[ ēŏn′ ]

The longest division of geologic time, containing two or more eras.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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