A person who believes in or studies aeons; someone preoccupied with extremely long periods of time.
From aeon + -ist (person who specializes in). The suffix -ist creates agent nouns, making this 'one who studies aeons.'
Aeonists might be philosophers pondering eternity or geologists measuring Earth's billions of years—both are wrestling with timescales that break the human brain. The Romantic poets were amateur aeonists, obsessed with ancient ruins and deep antiquity.
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