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 Much of its surface is encrusted with minerals that precipitated out of the seawater over eons, coating the lava at the excruciatingly slow rate of 1 centimeter or less every 1 million years. Warren Cornwall, Science | AAAS, "Mountains hidden in the deep sea are biological hot spots. Will mining ruin them?," 12 Sep. 2019 That was 10 years ago, a veritable eon for a modern-day outside linebacker. Los Angeles Times, "Clay Matthews plans to be a headliner again with the Rams," 5 Sep. 2019 Over the course of eons, uranium gradually breaks down into thorium. New York Times, "Overlooked No More: Elizabeth Rona, Pioneering Scientist Amid Dangers of War," 28 Aug. 2019 Back then, the comic potential of Nazis remained eons away from discovery. Ian Frazier, The New Yorker, "When W. E. B. Du Bois Made a Laughingstock of a White Supremacist," 19 Aug. 2019 In these fast-moving times, that would put them practically eons ahead of competitors relying purely on the imaginative powers of mere mortals. Ephrat Livni, Quartzy, "Alibaba designers used AI to shape New York Fashion Week looks," 7 Sep. 2019 That number was based on detailed studies of peak flows down the Colorado through history, both the 100 years of recorded history by man and the eons of geologic history recorded in the strata of the canyon walls. John D'anna, azcentral, "For a while in 1983, sheets of plywood were all that kept the mighty Glen Canyon Dam from overflowing," 18 July 2019 What Can the Moon Teach Us About the Early Solar System? The moon lacks much in the way of an atmosphere and hasn’t been volcanically active for billions of years, which means its surface has remained relatively unchanged across the eons. Daniel Oberhaus, WIRED, "Lunar Mysteries That Science Still Needs to Solve," 16 July 2019 Taken together, the geochemical and microfossil findings support his theory that during the Precambrian eon, complex life forms evolved not only in the oceans, but also on land. Peter Byrne, Quanta Magazine, "Early Life in Death Valley," 24 Apr. 2014

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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Statistics for eon

Last Updated

29 Oct 2019

Time Traveler for eon

The first known use of eon was circa 1642

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More Definitions for eon

eon

noun
How to pronounce eon (audio) How to pronounce eon (audio)

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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