eon
EE-on
/ˈiːən/
An indefinite and very long period of time; in geology, the largest unit of time.
Often used hyperbolically in speech to mean 'a very long time' (e.g., 'I haven't seen you in eons').
The story behind the word. From the Greek 'aion', which could mean a lifetime, a generation, or eternity. In Gnostic philosophy, 'Aeons' were divine beings that emanated from God. In the 19th century, geologists adopted it to describe the massive spans of Earth's history.
Word relationships
- age: An age is much shorter than an eon.
- eternity: Eternity is infinite; an eon is just very, very long.
- moment: A very brief period of time.
Commonly confused with
- era: An eon is made up of several eras.
Collocations
- geological eon
- for eons
- eons ago
Example sentences
- "The Archean eon saw the first appearance of life on Earth in the form of single-celled organisms." Geological history.
- "It feels like eons since we last had a proper summer vacation." Hyperbolic everyday use.
Memory hook
Eon is the longest word for the longest time (even though it's only 3 letters). The biggest bucket of time.
When not to use
Don't use it in scientific contexts unless you are referring to the specific geological unit (billions of years).
Fun facts
- There are only four recognized eons in Earth's history: Hadean, Archean, Proterozoic, and Phanerozoic.
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