Definition - Noun 1: the highest court in a nation or state specifcap S&C : the highest court in the judicial branch of the U.S. government that has original jurisdiction over controversies involving ambassadors or other ministers or consuls but whose main activity is as the court of last resort exercising appellate jurisdiction over cases involving federal law 2cap S&C: a court of original jurisdiction in New York The court of last resort in New York is the Court of Appeals.