Any of several species of fish found in the Atlantic Ocean off both the North American and European coasts. The king mackerel (also called kingfish) is probably the most well known of this family of fish. The mackerel has a firm, high-fat flesh with a pleasant savory flavor. When small (about 1 pound), it's sold whole. Larger fish are cut into fillets and steaks. Mackerel is also available smoked or salted. The latter must be soaked overnight before using to leach excess salt. Mackerel can be cooked in almost any manner including broiling, baking and sautéing. See also fish.