'autochthonal' originates from Greek, specifically the word 'autóchthōn' (αὐτόχθων), where 'auto-' meant 'self' and 'chthōn' meant 'earth' or 'soil'.

'autochthonal' changed from the Greek word 'autóchthōn' into Latinized forms and later English formations (via Medieval/Modern Latin and learned formations), with the adjectival suffix '-al' producing 'autochthonal' in modern English.

Initially it meant 'sprung from the land' (literally 'of the soil'), but over time it evolved into the broader modern meaning 'native' or 'indigenous' used for people, species, and geological features.