A more thorough explanation:

Definition: Commorientes are people who die at the same time, often due to the same cause. For example, if a married couple dies in a car accident, they are considered commorientes.

In civil law, there is a rule that determines who inherits property if commorientes die at the same time. This rule is called the "presumption of survivorship." It assumes that the older person died first, and their property goes to the younger person. This rule is important because it helps settle disputes over inheritance.

Example: John and Mary were a married couple who died in a house fire. Since they died at the same time, they are considered commorientes. The presumption of survivorship would apply to their estate, meaning that if John was older than Mary, his property would go to her, and then to her heirs.