A biopsy is done on a living patient, taking a small tissue sample to check for disease. An autopsy is done after death, to work out what caused it. The memory hook is in the roots: biopsy comes from bios, meaning “life,” while autopsy comes from autós, meaning “self,” as in seeing for yourself what happened.
The core difference
Biopsy examines the living; autopsy examines the dead.
- biopsy — a tissue sample taken from a living patient for diagnosis: The doctor ordered a biopsy to check for cancer.
- autopsy — an examination of a body after death to determine the cause: The coroner ordered an autopsy to confirm how the victim died.
How to tell them apart
The simplest test is who the procedure is for. If the person having tissue examined is still alive, it is a biopsy. If the examination happens after death, it is an autopsy, also called a post-mortem.
Autopsy has also picked up a figurative sense outside medicine, for a detailed after-the-fact review of a failure, as in “the team held a post-mortem autopsy on the failed product launch.” That usage keeps the core idea of looking back at something once it is already over.
