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narcolepsy

(Encyclopedia)narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and recurring unwanted episodes of sleep (“sleep attacks”). People with narcolepsy may abruptly fall asleep at almost any...

governor, device

(Encyclopedia)governor, automatic device used to regulate and control such variables as speed or pressure in the functioning of an engine or other machine. A governor may be an electric, hydraulic, or mechanical de...

giant African land snail

(Encyclopedia)giant African land snail, any of several species of large terrestrial snails of tropical Africa that have become agricultural pests in other regions of the world. The species include the giant African...

foot-and-mouth disease

(Encyclopedia)foot-and-mouth disease or hoof-and-mouth disease, highly contagious disease almost exclusive to cattle, sheep, swine, goats, and other cloven-hoofed animals. It is caused by a virus, specifically an a...

amortization

(Encyclopedia)amortization ămˌərtəzāˈshən, əmôrˈ– [key], reduction, liquidation, or satisfaction of a debt. The term amortization may also refer to the sum used for that purpose. The term is commonly us...

Fletcher, John

(Encyclopedia)Fletcher, John, 1579–1625, English dramatist, b. Rye, Sussex, educated at Cambridge. A member of a prominent literary family, he began writing for the stage about 1606, first with Francis Beaumont, ...

iritis

(Encyclopedia)iritis īrīˈtĭs [key], inflammation of the iris, the pigmented portion of the eye surrounding the pupil. The condition is sometimes associated with diabetes, with rheumatic diseases such as rheumat...

joint, in geology

(Encyclopedia)joint, in geology, fracture in rocks along which no appreciable movement has occurred (see fault). Nearly vertical, or sheet, joints that result from shrinkage during cooling are commonly found in ign...

apparition

(Encyclopedia)apparition, spiritualistic manifestation of a person or object in which a form not actually present is seen with such intensity that belief in its reality is created. The ancient and widespread belief...

June beetle

(Encyclopedia)June beetle or May beetle, a blackish or mahogany-colored beetle of the scarab beetle family, widely distributed in North America and especially abundant in the NE United States and the adjacent parts...