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multiple chemical sensitivity

(Encyclopedia)multiple chemical sensitivity (MCS), adverse physical reaction to certain chemicals in susceptible persons. When exposed to the chemicals, people with MCS react with symptoms such as nausea, headache,...

monorail

(Encyclopedia)monorail, railway system that uses cars that run on a single rail. Typically the rail is run overhead and the cars are either suspended from it or run above it. Driving power is transmitted from the c...

potentiometer

(Encyclopedia)potentiometer. 1 Manually adjustable, variable, electrical resistor. It has a resistance element that is attached to the circuit by three contacts, or terminals. The ends of the resistance element are...

thermostat

(Encyclopedia)thermostat, automatic device that regulates temperature in an enclosed area by controlling heating or refrigerating systems. It is commonly connected to one of these systems, turning it on or off in o...

photocopying

(Encyclopedia)photocopying, process whereby written or printed matter is directly copied by photographic techniques. Generally, photocopying is practical when just a few copies of an original are needed. When many ...

lighthouse

(Encyclopedia)lighthouse, towerlike structure erected to give guidance and warning to ships and aircraft by either visible or radioelectrical means. Lighthouses were long built to conform in structure to their geog...

air traffic control

(Encyclopedia)air traffic control, the system by which airplanes are safely routed into and out of major airports. Air traffic control in the United States is centered in a number of regional control centers that r...

Passion play

(Encyclopedia)Passion play, genre of the miracle play that has survived from the Middle Ages into modern times. Its subject is the suffering, death, and resurrection of Jesus. Passion plays were first given in Lati...

streetcar

(Encyclopedia)streetcar, small, self-propelled railroad car, similar to the type used in rapid-transit systems, that operates on tracks running through city streets and is used to carry passengers. Most often cars ...

suspension, in vehicles

(Encyclopedia)suspension, in automobiles, system of springs used to suspend the frame, body, engine, and power train above the wheels. Its principal purpose is to lessen the jarring of the automobile that is caused...