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hemophilia

(Encyclopedia)hemophilia hēˌməfĭlˈēə, –fēlˈyə [key], genetic disease in which the clotting ability of the blood is impaired and excessive bleeding results. The disease is transmitted through females but...

mass, in physics

(Encyclopedia)mass, in physics, the quantity of matter in a body regardless of its volume or of any forces acting on it. The term should not be confused with weight, which is the measure of the force of gravity (se...

arrhythmia

(Encyclopedia)arrhythmia ārĭᵺˈmēə [key], disturbance in the rate or rhythm of the heartbeat. Various arrhythmias can be symptoms of serious heart disorders; however, they are usually of no medical significan...

lava

(Encyclopedia)lava läˈvə [key], molten rock that erupts on the earth's surface, either on land or under the ocean, by a volcano or through a fissure. It solidifies into igneous rock that is also called lava. Bef...

work

(Encyclopedia)work, in physics and mechanics, transfer of energy by a force acting to displace a body. Work is equal to the product of the force and the distance through which it produces movement. Although both fo...

smoke

(Encyclopedia)smoke, visible gaseous product of incomplete combustion. Smoke varies with its source, but it usually comprises hot gas and suspended particles of carbon and tarry substances, or soot. To reduce the a...

steam engine

(Encyclopedia)CE5 Steam engine steam engine, machine for converting heat energy into mechanical energy using steam as a medium, or working fluid. When water is converted into steam it expands, its volume increa...

pearl, gem

(Encyclopedia)pearl, hard, rounded secretion formed inside the shell of certain mollusks, used as a gem. It is secreted by the epithelial cells of the mantle, a curtain of tissue between the shell and body mass, an...

moon

(Encyclopedia)CE5 The moon: Near side CE5 The moon: Far side moon, natural satellite of a planet (see satellite, natural) or dwarf planet, in particular, the single natural satellite of the earth. It is no...

chlorate

(Encyclopedia)chlorate pərklōrˈāt, –klôrˈ– [key], salts of chloric acid, HClO3, and perchloric acid, HClO4, respectively. Perchlorates are safer to handle than chlorates; they are more stable when expos...