thrush, bird, common name for members of the Turdidae, a large family of birds found in most parts of the world and noted for their beautiful song. The majority are modestly colored, with spotted underparts, in either the young or the adult stage, although some have bright plumage. Among these are the American robin, Turdus migratorius, largest of the thrushes, and the Eastern bluebird, Sialia sialis, bright blue with a red breast. Other thrushes found in North America are the wood, olive-backed, and gray-cheeked thrushes, the solitaire, and the veery, or Wilson's, thrush. The hermit thrush, a shy forest dweller, is the finest singer. The European "blackbird," the nightingale, the missel thrush, the stonechat, and the wheatear are thrushes. Thrushes are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Passeriformes, family Turdidae.

thrush, in medicine, infection caused by the fungus Candida albicans, manifested by white, slightly raised patches on the mucous membrane of the tongue, mouth, and throat. The mucous membrane beneath the patches is usually raw and bleeding. The overgrowth of this fungus results when the balance in the normal oral microbe population is disturbed by antibiotic therapy or disease. It occurs most frequently in infants, in adults suffering from chronic illnesses, in the debilitated, in the immunosuppressed, and in individuals on long-term antibiotic, corticosteroid, or antineoplastic therapy. It is often an early symptom of AIDS. Treatment is with antifungal drugs, such as nystatin.

mimic thrush, common name for members of the Mimidae, a family of exclusively American birds, allied to the wrens and thrushes, that includes the mockingbird, the catbird, and the thrashers. Mimic thrushes are most numerous in Mexico. They are about the size of a robin or slightly larger but are proportionately slimmer and have slender, down-curved bills, long tails which they twitch vigorously when excited, and strong legs suited to scratching through dead leaves and underbrush for insects; they also eat berries and fruit. All these birds are famous for their vocal powers. The preeminent songster of all North American birds is the common mockingbird, Mimus polyglottos, found in the E United States S of Maryland—the northernmost of nine similar species. It is gray above, with white wing patches and whitish underparts. Its song, usually delivered from a high, exposed perch, includes phrases from other birds' songs (of which it will repeat as many as 30 in succession), imitations of familiar sounds, and a melodious song of its own. Unmated males sing more than mated males and only unmated males sing at night in the spring. Two species of blue mockingbirds, genus Melanotis, are found in Mexico. Another member of the family, the catbird, Dumatella carolinensis, slate gray with a black cap and a chestnut patch under the tail, is also an expert singer, with a plaintive mewing call that gives it its name. Of the 17 species of thrashers, the brown thrasher, Toxostoma rufum, of the E United States is typical. It is a rich chestnut above, with whitish underparts streaked with brown; it is sometimes erroneously called the brown thrush. Thrashers also are tuneful singers and are valuable destroyers of harmful insects. Mimic thrushes are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Passeriformes, family Mimidae.

brown thrush: see mimic thrush.

Wilson's thrush: see thrush.

Any of about 300 species of songbirds (family Turdidae) that usually have a slender bill and “booted” lower legs (i.e., covered in front with one long scale instead of many short ones). Thrushes are 5–12 in. (13–30 cm) long. Most have dull plumage, often with patches of bright yellow, red, or blue. They are found virtually worldwide but are most diverse in the Old World, especially in Africa. The northern species are strong migrants. Occupying a wide range of arboreal and terrestrial habitats, thrushes eat insects and fruit; a few eat snails or earthworms. They lay three to six eggs in an open cup-shaped nest; a few occupy cavities. Some of the thrushes, including the hermit thrush and wood thrush, have notably beautiful songs. Seealso blackbird, bluebird, chat, ouzel, redstart, robin.

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