eon

noun

ˈē-ən  ˈē-ˌän 

variants or chiefly British aeon

1

: an immeasurably or indefinitely long period of time : age

I haven't seen him in eons.

2

a

: 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

The taste of each scoop is unique yet curiously delicious, everything working together in perfect harmony as if the combination was begging to be brought to life for eons. —Amanda Peukert, SPIN, 5 Sep. 2024

Cosmetics has had its hand in the game for what feels like eons now—the affordable beauty brand carved out a permanent spot in the drugstore market quite some time ago, and shows no signs of losing popularity. —Maya Gandara, StyleCaster, 3 Sep. 2024

Chiles, who won gold with the US team in Paris, placed third in the floor event finals on August 5 — what feels like eons ago in Olympic time. —Alex Abad-Santos, Vox, 12 Aug. 2024

And, for the first time in what seems like eons, there’s actual racing going on, with more than six different Grand Prix winners over the past seven Grand Prix races. —Sean Evans, Robb Report, 19 July 2024

Word History

Etymology

borrowed from Late Latin aeōn "age (in the world's history), evil spirit (in Gnosticism)," borrowed from Greek aiṓn "lifetime, long period of time, age" — more at aye entry 3

First Known Use

circa 1642, in the meaning defined at sense 1

Kids Definition

eon

noun

ˈē-ən

1

: a very long period of time

2

a

: a very large division of geologic time usually longer than an era

b

: a unit of geologic time equal to one billion years