killer whale or grampus, a large, rapacious marine mammal, Orcinus orca, of the dolphin family. Male killer whales may reach a length of 30 ft (9 m) and females half that length. The killer whale is black above, with a sharply contrasting white oval patch around each eye; its belly is white with white markings projecting up along the animal's sides. It has a high, triangular dorsal fin midway between head and tail, and broad, paddle-shaped flippers. The killer whale is worldwide in distribution. It is a swift and ferocious animal, armed with more than four dozen sharp teeth, and is the only cetacean (see whale) that feeds regularly on birds or mammals. Killer whales eat seals, sea birds, and fish, and in packs they will even attack larger whales. The female gives birth to a single calf, up to 7 ft (2.1 m) long, following a gestation period of approximately one year. Females mature in 6 to 7 years, males in 12. They are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Cetacea, family Delphinidae.

or orca

A species (Orcinus orca) of toothed whale found in all seas from the Arctic to the Antarctic. Largest of the dolphins, the male may be 30 ft (9 m) long and weigh over 10,000 lbs (4,500 kg). The killer whale is black, with white on the underparts, above each eye, and on each flank. The snout is blunt, and the strong jaws have 40–50 large, sharp, conical teeth. Killer whales live in groups of a few to about 50 individuals. They feed on fishes, cephalopods, penguins, and marine mammals; though they are fierce predators of seals and even other whales, there is no recorded instance of a killer whale attacking a human. They are often kept in captivity and trained as performers in marine shows.

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