Any of several species of large pelagic marine fish in the family Scombridae; worldwide distribution. Most species have high commercial importance, particularly Thunnus alalunga (albacore), T. obesus (bigeye tuna), T. albacares (yellowfin tuna) and Katsuwonus pelamis (skipjack tuna). Marketed in a variety of forms, including fresh and frozen (whole, gutted or fillets), canned, salted, dried and semi-preserved. Also used in a variety of prepared dishes, such as tuna sausages, tuna roll and tuna pastes. Also known as tunny.