'authigenetic' originates from Greek, specifically the word 'authigenēs', where 'auth-' meant 'self' and 'gen-' (from 'gignesthai'/'genes') meant 'born' or 'produced'. The English adjective formed via New Latin/Modern scientific coinage using the suffix '-etic'.

'authigenēs' (Greek) → New Latin/Modern scientific formation 'authigenic'/'authigenetic' → modern English 'authigenetic' used in geology and sedimentary petrology.

Initially it meant 'born in place' in the literal Greek sense; over time it has come to mean specifically 'formed in place' in geological contexts (i.e., minerals or sediments that developed where they are found).