eon

noun \ ˈē-ən , ˈē-ˌän \
variants: or chiefly British
Updated on: 12 Nov 2017

Definition of eon

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

Recent Examples of eon from the Web

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.

Origin and Etymology of eon

Latin, from Greek aiōn — more at 3aye


EON Defined for Kids

eon

Definition of eon for Students



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