Earth & SkyGreek → English
Aeon
/ˈiːɒn/noun
An immeasurably long stretch of time; in geology, one billion years.
The Greek roots
αἰών
aiṓn
lifetime, age
Literally: “an age”
Follow a root:αἰών2 words
The story of the word
In Homer αἰών is a person's allotted lifespan, the thing that leaves the body at death, with no sense of eternity about it. The meaning stretched through Hellenistic Greek to an age of the world, and Gnostic writers used it for emanations of the divine. Geologists have since pinned the word down to exactly a thousand million years, which is what a physicist means by it now.
- How it travelled
- Ancient Greek → Latin → English
- First recorded
- 17th century
In a sentence
The Proterozoic aeon lasted almost two billion years and left barely a fossil worth the name.