What is "tangfish"

Seal \Seal\ (s[=e]l), n. [OE. sele, AS. seolh; akin to OHG. selah, Dan. s[ae]l, Sw. sj["a]l, Icel. selr.] (Zo["o]l.) Any aquatic carnivorous mammal of the families Phocid[ae] and Otariid[ae].

Note: Seals inhabit seacoasts, and are found principally in the higher latitudes of both hemispheres. There are numerous species, bearing such popular names as sea lion, sea leopard, sea bear, or ursine seal, fur seal, and sea elephant. The bearded seal ( Erignathus barbatus), the hooded seal ( Cystophora cristata), and the ringed seal ( Phoca f[oe]tida), are northern species. See also Eared seal, Harp seal, Monk seal, and Fur seal, under Eared, Harp, Monk, and Fur. Seals are much hunted for their skins and fur, and also for their oil, which in some species is very abundant.

Harbor seal (Zo["o]l.), the common seal ( Phoca vitulina). It inhabits both the North Atlantic and the North Pacific Ocean, and often ascends rivers; -- called also marbled seal, native seal, river seal, bay seal, land seal, sea calf, sea cat, sea dog, dotard, ranger, selchie, tangfish.

n. (context UK dialect English) The common harbour seal.