- bluefin, bluefin tuna - flesh of very large tuna
--1 is a kind of tuna, tuna fish, tunny
--1 is a part of bluefin, bluefin tuna, horse mackerel, Thunnus thynnus - bluefin, bluefin tuna, horse mackerel, Thunnus thynnus - largest tuna; to 1500 pounds; of mostly temperate seas: feed in polar regions but breed in tropics
--2 is a kind of tuna, tunny
--2 is a member of Thunnus, genus Thunnus
--2 has parts: bluefin, bluefin tuna