Definition of eon
1 : an immeasurably or indefinitely long period of time : age I haven't seen him in eons.
2a : a very large division of geologic time usually longer than an era the Archean eonb : a unit of geologic time equal to one billion years
Origin and Etymology of eon
Latin, from Greek aiōn — more at 3aye
First Known Use: circa 1642
EON Defined for Kids
Definition of eon for Students
variant of aeon
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