plural tuna or tunas
1
: any of various large vigorous scombroid fishes (as of the genera Euthynnus, Katsuwonus, and especially Thunnus) that are usually dark above and silvery below and include many that are valued as food or sport fishes see albacore, bigeye tuna, bluefin tuna, dogtooth tuna, little tunny, skipjack tuna, yellowfin tuna
2
: the flesh of a tuna used for food
grilled tuna
specifically,
sometimes tuna fish
: tuna flesh that has been cooked and canned
—often used before another noun
tuna salad
a tuna fish sandwich
1
: any of various flat-jointed prickly pears (genus Opuntia)
especially
: one (O. tuna) of tropical America
2
: the edible fruit of a tuna
Cite this Entry
“Tuna.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tuna. Accessed 1 Nov. 2026.
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