shimmy a distinct vibration or side-to-side shaking of the front wheels, caused by a bent rim, a shifted tire belt, a loose suspension part, or a loose steering linkage part.
shock absorber a device placed at each wheel to help limit bounce and compression when driving over bumps or when stopping quickly.
slant engine an engine in which the cylinder block is slanted from the vertical.
sludge an engine-fouling conglomeration of oxidized oil, gas, and water that reduces lubricating efficiency.
spark plug a plug that screws into the cylinder head and delivers a spark to the combustion chamber to ignite the fuel-air mixture.
spoiler see airfoil.
springs any springlike devices, such as coil springs, leaf springs, or torsion bars, that absorb road shock.
stabilizer bar a shaft between the lower suspension arms that reduces swaying or lurching of the car on sharp turns or curves.
starter the small electric motor that turns the crankshaft to start the engine.
steering linkage the interconnections between the front wheels and the steering wheel.
stroke the distance of one stroke of a piston from the top to the bottom of a cylinder, or vice versa.
strut a shock absorber and mounting plate.
subcompact a very small, two-door, two-passenger car.
supercharger a device that pressurizes the air-fuel mixture to increase engine power.
suspension system collective term for the springs, shock absorbers, steering linkage, stabilizers, and torsion bars.
swaybar part of the suspension system, a stabilizing bar or rod mounted between wheels to reduce body lean when turning. Also known as an antiroll bar.
synchromesh a system that matches engine and gear speed to prevent grinding of the gears when shifting.
tachometer the rpm or engine speed gauge on the dashboard.
tailpipe the last portion of the exhaust system.
telematics generic term for remote services, such as Onstar, that work via GPS systems, mobile phone, and remote sensors.
toe in to align the front wheel so that they point inward slightly, for better handling at high speeds.
torque the turning or rotational force produced by an engine at the crankshaft.
torsion bar a bar that produces spring by twisting, especially over an uneven road.
transaxle on front-wheel drive or rear-engine cars, a unit that combines the functions of the transmission, differential, and clutch at the drive axle to eliminate the need for a driveshaft.
transmission the gear box that, through various gear ratios, transmits power from the engine to the drive axle.
transverse engine an engine mounted between the drive wheels, as in frontwheel drive cars.
tune-up a maintenance procedure in which parts of the ignition system are adjusted or replaced. A typical tune-up may include an adjustment of the idle speed, the fuel-air mixture and the timing, the gapping and replacement of spark plugs and points, and the replacement of the rotor and condenser.
turbocharger a supercharger powered by hot exhaust gases.
undercoating a rustproofing material applied underneath a car.
understeer a specific type of tire slippage common to front-wheel drive vehicles. In slick conditions, the vehicle continues on a straight path even after turning the steering wheel.
valves the engine devices that open and close to allow or stop the flow of fuel and air or exhaust gases.
V-8 an eight-cylinder engine, with the cylinders mounted in two rows forming an angle or V.
venturi in the carburetor, the narrowed passageway that creates a vacuum to draw fuel from the float bowl.
water jackets the engine channels through which coolant flows to cool the engine.
water pump the device that pumps coolant and water through the cooling system.
wheelbase the distance down the center from front axle to rear axle.
Zev zero emission vehicle, an electric or alternate- powered car producing no polluting exhaust.
Zipcar trade name of a company that, through membership, makes cars available for sharing at designated locations throughout the United States.
aviation
aerodynamics the branch of physics concerning the laws of motion of air under the influence of gravity or other forces.
aileron any one of the hinged movable surfaces or flaps on the trailing edge of a wing, used for executing banks or rolls.
airfoil any surface, such as a wing or an aileron, providing lift or aerodynamic control.
air speed indicator the instrument displaying air speed.
altimeter an instrument consisting of an aneroid barometer, used to determine altitude.
altitude the distance or height above land or water.
amphibian a plane equipped to take off or land on either water or land.