Tang

tang, in zoology

tang: see butterfly fish.

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surgeonfish

 or tang

Surgeonfish (Acanthurus leucosternon)

(credit: Jane Burton—Bruce Coleman Ltd.)

Any of about 75 species (family Acanthuridae) of thin, deep-bodied, tropical marine fishes that are small-scaled, with a single dorsal fin and one or more distinctive, sharp spines on either side of the tail base. The spines resemble a surgeon's scalpel and may be either fixed or hinged at the rear so that they can be opened outward and directed forward. Surgeonfishes are mostly algae eaters and usually do not exceed 20 in. (50 cm) long. The yellow surgeon, or yellow tang (Zebrasoma flavescens), is an Indo-Pacific species, and the blue tang (Acanthurus coeruleus) is found in the Atlantic and Caribbean.

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tang

the pointed end of a tool, such as a chisel, file, knife, etc., which is fitted into a handle, shaft, or stock

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tang [taŋ]

(engineering)

The part of a file that fits into a handle.

The end of a drill shank which allows transmission of torque from the drill press spindle to the body of the drill.

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tang

tang

The slender projecting tongue, or prong, forming part of one object that serves to secure it to another, as the projecting tongue on a chisel that secures it to a handle.

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T’ang 

a Chinese imperial dynasty that reigned from 618 to 907. The T’ang Dynasty was founded by Li Yuan. His son, Li Shih-min, united the country in 628, after subduing peasant insurgents and separatist feudal forces. He also strengthened the central authority and improved the organization of the military by instituting the fuping system.

During the reigns of the first T’ang emperors, a system of competitive state examinations was developed, which permitted the rise among the feudal class of an estate of scholars loyal to the imperial court; it was from this estate that members of the bureaucracy and the military elite were chosen. The same era saw the establishment of a system of allotment landowning called the equal-field system, which made it possible for the central government to regulate taxation.

A growing internal struggle among feudal groups resulted in a palace coup at the end of Emperor Li Chih’s reign (650–683). The emperor’s wife, Wu Tse-t’ien, seized power and ruled the country herself from 684 to 705. Until the middle of the eighth century, the T’ang Dynasty carried out an aggressive foreign policy that led to war and the seizure of neighboring lands. Later, the empire encountered resistance from the states of Nan Chao and T’ufan (Tibet) and the Uighur Khanate.

As the power of the dynasty waned in the middle of the eighth century, the power of the military governors (the chieh-tu-shih) increased—to the point where one governor, An Lu-shan, openly revolted. The dynasty’s dominance was ultimately broken by a peasant uprising led by Huang Ch’ao and his successors and by a struggle among various groups of the ruling class. Li Chu (904–907), the last T’ang emperor, was overthrown by the military commander Chu Wen. Earlier, Chu Wen, one of the leaders of the peasant uprising, had betrayed Huang Ch’ao by aligning himself with the emperor.

L. I. DUMAN