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arc, in electricity

(Encyclopedia)arc, in electricity, highly luminous and intensely hot discharge of electricity between two electrodes. The arc was discovered early in the 19th cent. by the English scientist Sir Humphry Davy, who so...

arc, in geometry

(Encyclopedia)arc, in geometry, a curved line or any part of it; in particular, a portion of the circumference of a circle. The length s of an arc of a circle of radius r and subtending a central angle of θ radian...

kite, in zoology

(Encyclopedia)kite, in zoology, common name for a bird of the family Accipitridae, which also includes the hawk. Kites are found near water and marshes in warm parts of the world. They prey chiefly on reptiles, fro...

labor, in economics

(Encyclopedia)labor, term used both for the effort of performing a task and for the workers engaged in the activity. In ancient times much of the work was done by slaves (see slavery). In the feudal period agricult...

lens, in optics

(Encyclopedia) CE5 Lenses lens, device for forming an image of an object by the refraction of light. In its simplest form it is a disk of transparent substance, commonly glass, with its two surfaces curved or wi...

larkspur, in botany

(Encyclopedia)larkspur, any north temperate, Old World annual of the genus Consolida of the buttercup family. Consolida species were formerly classified in the genus Delphinium, which includes similar annual, bienn...

larva, in zoology

(Encyclopedia)larva, independent, immature animal that undergoes a profound change, or metamorphosis, to assume the typical adult form. Larvae occur in almost all of the animal phyla; because most are tiny or micro...

laurel, in botany

(Encyclopedia) CE5 Sassafras, Sassafras albidum, a member of the laurel family laurel, common name for the Lauraceae, a family of forest trees and shrubs found mainly in tropical SE Asia but also abundant in tro...
 

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