A more thorough explanation:

Definition: Petens (pet-enz) is a Latin term used in history to refer to a demandant or a plaintiff in a real action.

Example: In medieval England, a person who wanted to claim ownership of a piece of land would file a real action in court. The person who filed the action was called the petens, or the plaintiff, while the person who was being sued was called the reus, or the defendant.

Explanation: The example illustrates how the term petens was used in medieval England to refer to a person who filed a real action in court. The petens was the one who was making the claim, while the reus was the one who was being sued. This term is no longer commonly used in modern legal systems, but it is still important to understand its historical significance.