'Arcadian' originates from Greek, specifically the word 'Arkádia' (Ancient Greek 'Ἀρκαδία'), where the name 'Arkas' referred to a mythological ancestor associated with that region.

'Arcadian' changed from Late Latin 'Arcadia' and Medieval/Modern Latin forms into Middle English 'Arcadia' and later the adjective/denonym 'Arcadian' in Early Modern English, eventually giving the plural 'Arcadians'.

Initially, it meant 'of or from the region Arcadia' (a place-name and its people), but over time it also acquired the sense 'idyllically rural, pastoral' and is used to evoke a simple, pastoral ideal.