Dolphin, the common name for a number of small whales, also called porpoises. They are not fishes, but mammals. They are dusky above and whitish below, and attain a length of six feet and more. The snout is prolonged into a slender beak, and the mouth is provided with teeth — an unusual thing among whales. They swim rapidly, and are often seen from the deck of ocean-steamers, swimming on the surface and leaping slightly from the water. The name dolphin is also applied by sailors to a true fish that changes its colors when taken from the water, and is on that account celebrated in literature.
