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nail, in anatomy

(Encyclopedia)nail, in anatomy, the horny outgrowth shielding the tip of the finger and the toe in humans and most other primates. The nail consists of dead cells pushed outward by dividing cells in the root, a fol...

Augustine of Canterbury, Saint

(Encyclopedia)Augustine of Canterbury, Saint ôˈgəstēn, –tĭn; ôgŭsˈtĭn [key], d. c.605, Italian missionary, called the Apostle of the English, first archbishop of Canterbury (from 601). A Roman monk, he w...

imprinting

(Encyclopedia)imprinting, acquisition of behavior in many animal species, in which, at a critical period early in life, the animals form strong and lasting attachments. Imprinting is important for normal social dev...

thresher shark

(Encyclopedia)thresher shark, long-tailed, warm-water shark, genus Alopias. The upper fork of its tail is slender and sickle-shaped and is about equal in length to the rest of the body. This shark uses its tail str...

gerbil

(Encyclopedia)gerbil jûrˈbĭl [key], small desert rodent found throughout the hot arid regions of Africa and Asia. Also known as sand rats, gerbils have large eyes and powerful, elongated hind limbs upon which th...

anaphylaxis

(Encyclopedia)anaphylaxis ănˌəfəlăkˈsĭs [key], hypersensitive state that may develop after introduction of a foreign protein or other antigen into the body tissues. When an anaphylactic state exists, a secon...

fiat money

(Encyclopedia)fiat money fīˈət, fīˈăt [key], inconvertible money that is made legal tender by the decree, or fiat, of the government but that is not covered by a specie reserve. It is commonly understood to b...

aardwolf

(Encyclopedia)aardwolf ärdˈwo͝olf [key], carnivore of the hyena family. The aardwolf, Proteles cristatus, resembles the true hyena but is smaller and more delicate. It has less powerful teeth and jaws and five i...

Eustachian tube

(Encyclopedia)Eustachian tube yo͞ostāˈshən [key] [for Bartolomeo Eustachi], a hollow structure of bone and cartilage extending from the middle ear to the rear of the throat, or pharynx, technically known as the...

treehopper

(Encyclopedia)treehopper, any member of three families of winged insects, remarkable for the curious shapes of most species. The shapes are due to the enlargement of the dorsal (upper) covering of the first thoraci...