cassowary, common name for a flightless, swift-running, pugnacious forest bird of Australia and the Malay Archipelago, smaller than the ostrich and emu. The plumage is dark and glossy and the head and neck unfeathered, wattled, and brilliantly colored, with variations in the coloring in different species. The head bears a horny crest. The female is larger than the male, though both sexes are similar in color. They are monogamous and nest in shallow nests of leaves on the ground in forests. Only the male incubates the female's three to six dark-green eggs. Cassowaries are primarily nocturnal. Their diet consists mainly of fruits and berries, although some eat insects and small animals. Cassowaries are notoriously vicious and have attacked and killed men with their sharp, spikelike toenails. They are fast runners, attaining speeds up to 30 mi (48 km) per hr. Cassowaries are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Struthioniformes, family Casuariidae.

Any of several species of ratite (family Casuariidae) of the Australo-Papuan region. Related to the emu, it has been known to kill humans with slashing blows of its feet, which have long, daggerlike claws on the innermost toe. It has a featherless blue head protected by a bony crest and has a black body (immature birds are brownish). It moves rapidly along narrow tracks in the bush. Cassowaries eat fruit and small animals. The largest species is the common, or southern, cassowary (Casuarius casuarius), which stands almost 5 ft (1.5 m) tall.

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