Hunting is an activity that usually involves tracking down an animal with the objective of killing or capturing it. Being skilled in tracking is very important when hunting. For some, especially in modern times, hunting is just a game, done for sport. But for others, especially in the old days, hunting is a way of life, as the animals that they hunt are used for food.
Someone who tracks down criminals could also be considered a hunter. And a criminal who stalks and murders someone could also be engaged in a "hunt." There are many superheroes and supervillains alike who are skillful hunters.