tuna
(also called ‘tunafish’, ‘tunny’; plural – ‘tuna’ or ‘tunas’; pronunciation: the letters ‘tu’ rhyme with the word “too” or with the letters ‘tu’ in “tune” — for the two different pronunciations, please click here)

a kind of fish – salt water – bony, finned & scaly – related to the mackerels – stout body with pointed snout (= mouth and nose part), very narrow tail part, sharp fins with short spines on the back part, crescent-shaped tail; size: (vary widely) the smallest – the blackfin tuna – 3-4 feet in length and 15-20 Kg. in weight, and the largest – the bluefin tuna – 6-10 feet in length and 500-650 Kg. in weight; feeds on (eats) zooplankton (= very small water animals), fish, shellfish, squid; lives for (lifespan, too, varies widely) the shortest lived – the skipjack (tuna) 3 years, and the longest lived – the bluefin tuna 30 years; about 48 species (?) found in most parts of the oceans

(tinned/canned tuna)
The tuna fish are a popular sport and food fish.
Tuna are canned/tinned and sold all over world.

(tuna cactus)
tuna (noun) = the vagina (= the sex organ of a woman — not to be used in formal situations)
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