aeon

/ˈiːɒn/
noun
  1. An extremely long period of time; thousands or millions of years.
    • It felt like an aeon had passed before the bus finally arrived.
    • The mountains have stood here for aeons, slowly worn down by wind and rain.
    • Geologists study rocks that formed over aeons beneath the ocean.
  2. A very long, indefinite period of time in mythology or cosmology.
    • The idea of an eternal aeon fascinates people who think about time and creation.
    • Some philosophers believe the universe goes through endless cycles, each aeon lasting billions of years.
    • In ancient Greek myth, each aeon was ruled by a different god.
Antonyms
What does "aeon" mean? | whatsthatwordmean | whatsthatwordmean