ostrich

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A large, swift-running flightless bird (Struthio camelus) of Africa, characterized by a long bare neck, small head, and two-toed feet. It is the largest living bird.
2. n. A rhea.
3. n. One who tries to avoid disagreeable situations by refusing to face them.

Century Dictionary and Cyclopedia

1. n. A very large ratite bird of the genus Struthio. The true or African ostrich (S. camelus) inhabits the sandy plains of Africa and Arabia, and is the largest of all existing birds, attaining a height of from 6 to 8 feet. The head and neck are nearly naked, and the quill-feathers of the wings and tail have their barbs wholly disconnected. It is chiefly for these plumes, which are highly esteemed as articles of dress and decoration, that the bird is hunted and also reared in domestication. The legs are extremely strong, the thighs are naked, and the tarsi are covered with scales. There are only two toes, the first and second being wanting. The pubic bones are united — a conformation occurring in no other bird. The wings are of small size and incapable of being used as organs of flight; the birds can run with extraordinary speed, distancing the fleetest horse. The food consists of grass, grain, and other substances of a vegetable nature. Ostriches are polygamous, every male consorting with several females, and they generally keep together in larger or smaller flocks. The eggs are of great size, averaging three pounds each in weight, and several hens often lay in the same nest, which is merely a hole scraped in the sand. The eggs appear to be hatched mainly by incubation, both parents relieving each other in the task, but also partly by the heat of the sun. The South African ostrich is often considered as a distinct species under the name of S. australis. Three South American birds of the genus Rhea are popularly known as the American ostrich, though they are not very closely allied to the true ostrich, differing in having three-toed feet and in many other respects. The best-known of the three is R. americana, the nandu or nanduguaçu of the Brazilians, in habiting the great American pampas south of the equator. It is considerably smaller than the true ostrich, and its plumage is much inferior. R. darwini, a native of Patagonia, is still smaller, and belongs to a different subgenus (Ptilocnemis). The third species is the R. macrorhyncha, so called from its long bill; it is perhaps only a variety of the first.
2. n. Four species of ostriches are now recognized, the name Struthis camelus being restricted to the northern species that ranges into Arabia. S. molybdophanes is from Somaliland, and S. meridionalis or masaicus from Central Africa. The southern species, S. australis, is the one that has been partially domesticated and is kept in ostrich-farms for the sake of its feathers. The eggs of these species differ quite as much as do the birds themselves, that of S. camelus being quite smooth while the others are more or less deeply pitted.

Wiktionary

1. n. A large flightless bird (Struthio camelus) native to Africa.

GNU Webster's 1913

1. n. (Zoöl.) A large bird of the genus Struthio, of which Struthio camelus of Africa is the best known species. It has long and very strong legs, adapted for rapid running; only two toes; a long neck, nearly bare of feathers; and short wings incapable of flight. The adult male is about eight feet high.

WordNet 3.0

1. n. fast-running African flightless bird with two-toed feet; largest living bird
2. n. a person who refuses to face reality or recognize the truth (a reference to the popular notion that the ostrich hides from danger by burying its head in the sand)