'atlantean' originates from Modern English formation based on 'Atlantis' (from Greek 'Ἀτλαντίς' / 'Atlantis'), where 'Atlant-' referred to 'of Atlas' (the mythic figure associated with the Atlantic/sea).

'atlantean' was formed in English from the classical name 'Atlantis' (Greek 'Ἀτλαντίς'), through Latin 'Atlantis', and later adapted with the adjectival suffix '-ean' to create 'atlantean' in modern English.

Initially the root referred to 'of Atlas' or the region associated with Atlas; over time the English adjective 'atlantean' came to mean specifically 'relating to the legendary island of Atlantis' and its purported culture.