'autopsist' is formed from the noun 'autopsy' plus the agent suffix '-ist'. 'Autopsy' comes from Greek 'autopsia' (αὐτοψία), where 'autos' meant 'self' and 'opsis' meant 'seeing'.

'autopsy' entered English via Medieval Latin/Old French from Greek 'autopsia' meaning 'seeing with one's own eyes'. The agent-form 'autopsist' was later formed in English by adding the suffix '-ist' to indicate a person who performs or specializes in autopsies.

Originally 'autopsy' meant 'to see for oneself'; over time it became specialised to mean a postmortem examination of a body, and 'autopsist' came to mean 'one who performs such an examination'.