1) Commercial fish 2) Fish genus 3) Genus thunnus 
Thunnus is a genus of ocean-dwelling ray-finned bony fish from the Scombridae (Mackerel) family. More specifically, Thunnus is one of five genera which comprise the Thunnini tribe – a tribe that is collectively (and famously) known as the tunas. Also called the true tunas or real tunas, Thunnus consists of eight species of tuna (more than half o...[subgenus] Thunnus (Thunnus) is a subgenus of ray-finned bony fishes in the Thunnini, or tuna, tribe. More specifically, Thunnus (Thunnus) is a subgenus of the genus Thunnus, also known as the `true tunas`. Thunnus (Thunnus) is sometimes referred to as the bluefin group, and comprises five species: ...
[n] - tunas: warm-blooded fishes
genus Thunnus noun tunas: warm-blooded fishes