Eon Definition & Meaning

American

British

Scientific

Usage

Etymology

Examples

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 / ē′ŏn′ /

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.

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

Quantum computers are seen as a critical next-generation technology because they can quickly perform computations that would take today’s computers eons.

From The Wall Street Journal

After reviewing the recreation of the photo — the architects are still smiling this time, but their scrappy overconfidence feels eons away — Pildas wonders who the next generation will be, and how they will rise.

From Los Angeles Times

Us film fans have stared at his hawkish mug for eons, but I can’t remember ever before seeing him flash a huge, daffy grin.

From Los Angeles Times

Wanting to leave but feeling trapped in your dynamic is a distinctly human nightmare that has pervaded our species and plagued our ancestors for eons.

From Salon

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.