Aeon
noun /ˈiː.ɒn/ — An immeasurably long period of time; eternity.
Definition
An indefinite and very long period of time — often used hyperbolically to mean an eternity. In geology, an aeon is a unit of time equal to one billion years. In some philosophical and religious traditions, an aeon is a divine emanation.
Beyond the definition
An aeon makes your lifetime a breath. It puts everything in perspective — not nihilistically, but humbly. Whatever we are doing, we are doing it in the briefest imaginable moment of cosmic time.
Origin & history
Greek: 'aiōn' (age, lifetime, eternity). Related to Latin 'aevum' (age). In Gnostic thought, an aeon is a divine power or essence. The same root gives us 'medieval' (middle age).
Example sentences
Illustrative sentences for learning, not verified community posts or sourced quotations.
It felt like aeons had passed since the last time she had been genuinely still.
The canyon was carved over aeons — the river's patient work measured in millions of years.
An aeon of evolutionary pressure had produced the eye's extraordinary complexity.
How to use it
This entry uses a noun. Follow the examples for articles and singular or plural forms; not every noun takes “a” or “an.”
Choose “Aeon” when the meaning fits your context: An indefinite and very long period of time — often used hyperbolically to mean an eternity. In geology, an aeon is a unit of time equal to one billion years. In some philosophical and religious traditions, an aeon is a divine emanation.
Synonyms
eternity, age, millennium, epoch
Antonyms
instant, moment, flash
Related words
Aeon vs eternity
An aeon refers to an immeasurably long, but finite, period of time. Eternity refers to a state of existence that has no beginning and no end.
Word in the Wild
See how this word appears in life, language and stories.
Illustrative sentences and imagined stories for learning — not verified sightings, interviews, or sourced quotations.
Fictional scene
Observatory Under Night Sky
An adult at a telescope, with a solar-system mobile, crescent moon, and a distant galaxy beyond the window.
The vast distance of the galaxy and the scale of the planets represent the concept of an aeon, suggesting a period of time so indefinite and long that it transcends human perception.
Image credit: Wordspun · AI-generated conceptual illustration
Questions about this word
What does "Aeon" mean?
Aeon is noun meaning: An immeasurably long period of time; eternity.. An indefinite and very long period of time — often used hyperbolically to mean an eternity. In geology, an aeon is a unit of time equal to one billion years. In some philosophical and religious traditions, an aeon is a divine emanation.
Where does the word "Aeon" come from?
Greek: 'aiōn' (age, lifetime, eternity). Related to Latin 'aevum' (age). In Gnostic thought, an aeon is a divine power or essence. The same root gives us 'medieval' (middle age).