Answer: The term that describes a final decision of a court that is conclusive on all issues between the parties, whether raised in the litigation or not, is "res judicata." This legal principle means that a final decision on a cause of action by a competent court cannot be litigated again by the parties in a new proceeding, either in the same court or any other court. Res judicata ensures the finality of court decisions and helps to promote the efficient resolution of disputes, as parties are generally not allowed to re-litigate the same issues repeatedly.