What is the term for the postmortem evacuation of substances from an external orifice of the body?

The term for the postmortem evacuation of substances from an external orifice of the body is "purge." This describes the process in which fluids and gases are expelled from the body after death, which can occur due to natural decomposition processes and the breakdown of bodily tissues. Purging typically happens from body orifices such as the mouth, nose, or rectum. Understanding this term is crucial for those in the field of mortuary science, as it relates to both the physical changes that occur in a body following death and the implications for embalming and funeral practices.

Other terms in the question, such as excretion, generally refer to the elimination of waste during life and are not applicable postmortem. Decomposition relates more broadly to organic breakdown processes after death rather than specifically to the evacuation of substances. Evacuation, while it may sound similar, is too generalized and does not specifically encapsulate the distinct process of purging that takes place with a postmortem context.