1650s, "an eye-witnessing," from Modern Latin autopsia, from Greek autopsia "a seeing with one's own eyes," from autos- "self" (see auto-) + opsis "a sight" (see eye (n.)). Sense of "dissection of a body to determine cause of death" is first recorded 1670s, probably from the same sense in French autopsie (1570s).
autopsy au·top·sy (ô'tŏp'sē, ô'təp-)
An examination of a cadaver in order to determine the cause of death or to study pathologic changes. Also called necropsy, postmortem, postmortem examination.