'auto-' originates from Greek, specifically the word 'autos', where 'auto-' meant 'self'.

'auto-' entered English in modern scientific and learned coinages (18th–19th centuries) from Greek 'autos' via New Latin and Neo‑Greek formations (e.g. 'autograph', 'automatic').

Initially it meant 'self' in the literal sense; over time its use broadened into related senses such as 'self-acting' or 'automatic' in technical and everyday words.