Aeon
WordNet
noun
(1) (Gnosticism) a divine power or nature emanating from the Supreme Being and playing various roles in the operation of the universe
(2) An immeasurably long period of time
"Oh, that happened eons ago"
(3) The longest division of geological time
WiktionaryText
Noun
- An extended period of time. Usually assumed to be more than a millennium.
- A spirit in Gnosticism