pilot whale 
noun
A toothed whale that has black skin with a grey anchor-shaped marking on the chin, a low dorsal fin, and a square bulbous head. Also called blackfish.
- Genus Globicephala, family Delphinidae: the short-finned G. macrorhyncus of subtropical waters, and the long-finned G. melas of temperate waters.
- In June, along the shoreline of Mauritania, in northwest Africa, scientists made a gruesome discovery: the carcasses of 230 dolphins, a pilot whale, and 15 endangered hawksbill and leatherback sea turtles.
- Despite their names, some of these are really types of dolphin, as is the short-finned pilot whale.