eon

noun
\ ˈē-ən How to pronounce eon (audio) , ˈē-ˌän How to pronounce eon (audio) \
variants: or chiefly British

Definition of eon

1 : an immeasurably or indefinitely long period of time : age I haven't seen him in eons.
2a : a very large division of geologic time usually longer than an era the Archean eon
b : a unit of geologic time equal to one billion years

Examples of eon in a Sentence

Recent Examples on the Web

Animals adapt over eons to be perfectly suited to their natural environments. Natasha Daly, National Geographic, "Meet the animals that survive extreme desert conditions," 25 Apr. 2019 In the standard paradigm of the Hadean eon, these strikes culminated in an assault dubbed the Late Heavy Bombardment, also known as the lunar cataclysm, in which asteroids emigrated to the inner solar system and pounded the rocky planets. Quanta Magazine, "Fossil Discoveries Challenge Ideas About Earth’s Start," 22 Jan. 2018 This far from base reality, the haywire way that things go—Rhea’s death, the narrow and fragile window of our moment in all the cold eons, even Little Sister ravening to survive—make a kind of sense now. Smith Henderson, Popular Mechanics, "Olympia," 20 Nov. 2017 Over eons, plant and animal remains (not to mention hominins) have been found in the caves. Lydia Pyne, Ars Technica, "Rising Star found a new species—now it wants to find a new way for paleoanthropology," 20 Dec. 2018 Through eons of incremental innovation, a cave dweller’s sketching stick evolved into the No. Robert Lee Hotz, WSJ, "Is This the World’s Oldest Hashtag?," 12 Sep. 2018 These monoliths, eroded by nature over the eons into curious shapes, are a defining feature of Hampi, the erstwhile seat of the Vijayanagara Empire in the Southern Indian state of Karnataka. Sarah Khan, Condé Nast Traveler, "Visiting Hampi, an Historic Region of Southern India That's Free of Tourists...For Now," 1 Aug. 2018 Ten miles across and 3,500 feet deep, it’s been carved out over eons by lava flows and water pouring down from the summit of Wai'ale'ale. Cnt Editors, Condé Nast Traveler, "The Best Islands in the U.S.: 2018 Readers' Choice Awards," 9 Oct. 2018 The challenge of visualizing things like light-years and eons, which our brains just weren’t meant to comprehend, is that they weren’t really meant to exist on Earth. Kevin Dupzyk, Popular Mechanics, "How to Make a Scale Model of the Universe," 21 Aug. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'eon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of eon

circa 1642, in the meaning defined at sense 1

History and Etymology for eon

Latin, from Greek aiōn — more at aye entry 3

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Dictionary Entries near eon

Eolithic

eolotropic

EOM

eon

eonian

eo nomine

Eopaleozoic

Statistics for eon

Last Updated

9 Jul 2019

Look-up Popularity

Time Traveler for eon

The first known use of eon was circa 1642

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More Definitions for eon

eon

noun

English Language Learners Definition of eon

: a very long period of time

eon

Kids Definition of eon

variant of

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More from Merriam-Webster on eon

Rhyming Dictionary: Words that rhyme with eon

Spanish Central: Translation of eon

Nglish: Translation of eon for Spanish Speakers

Britannica English: Translation of eon for Arabic Speakers

Britannica.com: Encyclopedia article about eon

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