Source : Webster's Revised Unabridged Dictionary (1913)

Eon \E"on\, AEon \[AE]"on\, n. [L. aeon, fr. Gr. a'iwn space or
   period of time, lifetime, age; akin to L. aevum. See {Age}.]
   1. An immeasurable or infinite space of time; eternity; a
      long space of time; an age.

            The eons of geological time.          --Huxley.

   2. (Gnostic Philos.) One of the embodiments of the divine
      attributes of the Eternal Being.

            Among the higher [AE]ons are Mind, Reason, Power,
            Truth, and Life.                      --Am. Cyc.

   Note: Eons were considered to be emanations sent forth by God
         from the depths of His grand solitude to fulfill
         various functions in the material and spiritual
         universe.

Source : WordNet®

eon
     n 1: the longest division of geological time [syn: {aeon}]
     2: an immeasurably long period of time [syn: {aeon}]
     3: (Gnosticism) a divine power or nature emanating from the
        Supreme Being and playing various roles in the operation
        of the universe [syn: {aeon}]