Definitions of post-mortem
(also: post-mortem examination) the examination of a dead body to find out why the person died. The term is also used in reference to animals.
A post-mortem examination has failed to show a conclusive cause of death and further tests are being carried out.
the analysis or discussion of an event shortly after it has happened, especially to find out why the event failed
Further post-mortem changes to the company's management are expected following the mailed merger talks.