Relating to or composed of ether; existing in or inhabiting the upper air or heavens.
From aether (Greek/Latin for upper air) plus -an (suffix meaning 'of or relating to'). Related to celestial and heavenly realms.
The 'etherean' spelling is quite rare, but it pops up in 19th-century spiritualist literature and science fiction describing beings from the heavens — it's the kind of word that tells you exactly what era a text comes from.
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