ETYM Latin aeon, from Greek aion space or period of time, lifetime, age; akin to Latin aevum. Related to Age.
1. The longest division of geological time; two or more eras; SYN. aeon. (Phanerozoic, Proterozoic, Archean, Hadean).
2. An immeasurably long period of time; SYN. aeon.
3. (In Gnosticism) A divine power or nature emanating from the Supreme Being and playing various roles in the operation of the universe; SYN. aeon.