Blackfish \Black"fish\, n.

1. (Zo["o]l.) A small kind of whale, of the genus Globicephalus, of several species. The most common is G. melas. Also sometimes applied to other whales of larger size.

2. (Zo["o]l.) The tautog of New England (Tautoga).

3. (Zo["o]l.) The black sea bass (Centropristis atrarius) of the Atlantic coast. It is excellent food fish; -- locally called also black Harry.

4. (Zo["o]l.) A fish of southern Europe (Centrolophus pompilus) of the Mackerel family.

5. (Zo["o]l.) The female salmon in the spawning season.

Note: The name is locally applied to other fishes.

Source: Webster's Revised Unabridged Dictionary (1913)