'autochthonic' originates from Greek, specifically the word 'autokhthōn' (αὐτόχθων), where 'auto-' meant 'self' and 'khthōn' meant 'earth'.

'autokhthōn' passed into Late Latin and New Latin as 'autochthon' and through scholarly Latin and English usage developed into the modern adjective 'autochthonic'.

Initially it meant 'of or from the native soil' and over time it has retained and specialized to mean 'native, indigenous' or 'formed in place' in scientific contexts.