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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...

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...

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...

lake, in dyeing

(Encyclopedia)lake, in dyeing, an insoluble pigment formed by the reaction between an organic dye and a mordant. The color of a lake depends upon the mordant as well as the dye used. Generally, lakes are not as col...

mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

mole, in zoology

(Encyclopedia)mole, in zoology, common name for the small, burrowing, insectivorous mammals of the family Talpidae, found throughout the temperate Northern Hemisphere. Moles are trapped as pests, although they prob...

monitor, in zoology

(Encyclopedia)monitor, any of various, mostly tropical lizards. A monitor lizard has a heavy body, long head and neck, long tail that comes to a whiplike end, and strong legs with sharp claws. Its slender, forked t...

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