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Synonyms

eon

American  
[ee-uhn, ee-on] / ˈi ən, ˈi ɒn /
Or aeon

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.


eon British  
/ ˈiːən, ˈiːɒn /

noun

  1. the usual US spelling of aeon

  2. 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

eon Scientific  
/ ēŏn′ /
  1. The longest division of geologic time, containing two or more eras.


Usage

What does eon mean? Eon is commonly used in a general way to refer to an indefinitely long period of time. Outside of science, people usually use eon as a way to exaggerate how long something took to happen or how long something lasted.In the context of geology, eon refers to the largest division of geological time. Technically speaking, an eon is made up of two or more eras, which consist of several periods, which are divided into epochs.All of these units of time vary as to their exact length, but most consist of at least millions of years, with eons lasting billions or hundreds of millions of years.In the context of astronomy, an eon is one billion years.Example: It took me eons to get a straight answer as to how long an eon actually is.

Etymology

Origin of eon

aeon

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Their offspring range from 6 months to 26 years old—eons in AI terms.

From The Wall Street Journal

What meaning did individual human life have in a vast universe that had existed for incalculable eons?

From The Wall Street Journal

For eons, most investors treated hot stocks the same way.

From Barron's

“We’ve had multiracial relationships in our family for eons,” she says.

From Los Angeles Times

The dot-com bubble was nearing its peak 26 years ago, and on Wall Street, where most careers are not even measured in decades, that’s eons ago.

From MarketWatch