Eon - definition of eon by The Free Dictionary
e·on also ae·on (ē′ŏn′, ē′ən) n. 1. An indefinitely long period of time; an age. 2. The longest division of geologic time, containing two or more eras. [Late Latin aeōn, from Greek aiōn; see aiw-in Indo-European roots.] eon (ˈiːən; ˈiːɒn) n the usual US s...