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bleaching

(Encyclopedia)bleaching, process of whitening by chemicals or by exposure to sun and air, commonly applied to textiles, paper pulp, wheat flour, petroleum products, oils and fats, straw, hair, feathers, and wood. C...

ectoderm

(Encyclopedia)ectoderm, layer of cells that covers the surface of an animal embryo after the process of gastrulation has occurred. This outer layer, together with the endoderm, or inner layer, is present in all ear...

hummingbird

(Encyclopedia)hummingbird, common name for members of the family Trochilidae, small, strictly New World birds, related to the swifts, and found chiefly in the mountains of South America. Hummingbirds vary in size f...

hoatzin

(Encyclopedia)hoatzin wätsēnˈ [key] [Aztec], common name for a peculiar marsh bird, Opisthocomus hoatzin. The hoatzin is a slender bird with a brownish plumage spotted with white above and reddish-yellow to rust...

rhea, in zoology

(Encyclopedia)rhea rēˈə [key], common name for a South American bird of the family Rheidae, which is related to the ostrich. Weighing from 44 to 55 lb (20–25 kg) and standing up to 60 in. (152 cm) tall, the rh...

owl

(Encyclopedia)owl, common name for nocturnal birds of prey found on all continents. Owls superficially resemble short-necked hawks, except that their eyes are directed forward and are surrounded by disks of radiati...

woodpecker

(Encyclopedia)woodpecker, common name for members of the Picidae, a large family of climbing birds found in most parts of the world. Woodpeckers typically have sharp, chisellike bills for pecking holes in tree trun...

pterosaur

(Encyclopedia)pterosaur tĕrˈəsôrˌ [key] [Gr., = winged lizard], extinct flying reptile (commonly called pterodactyl [Gr., = wing finger]) of the order Pterosauria, common in the late Triassic and Creta...

goatsucker

(Encyclopedia)goatsucker, common name for nocturnal or crepuscular birds of the order Caprimulgiformes, which includes the frogmouth, the oilbird, potoos, and nightjars. Goatsuckers are medium in size and are found...

insulation

(Encyclopedia)insulation ĭnˌsəlāˈshən, ĭnˌsyo͝o– [key], use of materials or devices to inhibit or prevent the conduction of heat or of electricity. Common heat insulators are, fur, feathers, fiberglass, ...
 

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