Dictionary.com
definitions
  • synonyms

eon

or ae·on

[ee-uh n, ee-on]
See more synonyms for eon on Thesaurus.com
noun
  1. an indefinitely long period of time; age.
  2. the largest division of geologic time, comprising two or more eras.
  3. Astronomy. one billion years.
Show More

Origin of eon

see origin at aeon
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words

ages, aeon

Examples from the Web for eon

Contemporary Examples

Historical Examples


British Dictionary definitions for eon

eon

noun
  1. the usual US spelling of aeon
  2. geology the longest division of geological time, comprising two or more eras
Show More
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

Word Origin and History for eon

n.

1640s, from Latin aeon, from Greek aion "age, vital force, a period of existence, lifetime, generation;" in plural, "eternity," from PIE root *aiw- "vital force, life, long life, eternity" (cf. Sanskrit ayu "life," Avestan ayu "age," Latin aevum "space of time, eternity," Gothic aiws "age, eternity," Old Norse ævi "lifetime," German ewig "everlasting," Old English a "ever, always").

Show More
Online Etymology Dictionary, © 2010 Douglas Harper

eon in Science

eon

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