eonian

also
adj.
Of, relating to, or constituting an eon.

Note: click on a word meaning below to see its connections and related words.

The adjective has 2 meanings:

Meaning #1: of or relating to a geological eon (longer than an era)
  Synonym: aeonian
  Pertains to noun: eon (meaning #1)

Meaning #2: lasting for an indefinitely long period of time
  Synonyms: everlasting, eternal, lasting, aeonian

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