WordWeb Online

1. An immeasurably long period of time
   "oh, that happened aeons ago";
   - eon
    
2. The longest division of geological time
   - eon
    
3. (Gnosticism) a divine power or nature emanating from the Supreme Being and playing various roles in the operation of the universe
   - eon

Derived forms: aeons

Type of: age, donkey's years [Brit, informal], geologic time, geological time, lifetime, long time, spiritual being, supernatural being, years, yonks [Brit, informal]

Encyclopedia: Aeon