Etymology Borrowed from United States Spanish tuna, alteration of Spanish atún, from Arabic اَلتُّنّ (at-tunn, “tuna”), from Latin thunnus, itself from Ancient Greek θύννος (thúnnos). Possibly in the sense of "darter" from thynein "to dart along". Doublet of tonno.
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Any of several species of fish of the genus Thunnus in the family Scombridae.
Tuna was carried down by the flood; and when Maui saw him in the net he stretched forth his arm and with a blow of his stone axe smote Tuna and cut off his head, and it and the tail fell into the ocean. ... The head became fish, and the tail became the koiro (ngoiro—conger-eel).1887, John White, The Ancient History of the Maori, page 84: