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A Glossary of Automotive Terms


Word for car nerds (and used car shoppers)

A Glossary of Automotive Terms | CarMax

Looking for a used car and curious about all those terms? What’s ‘AWD’ mean, for example? How about horsepower? Read on, and be in the know!


An anti-lock braking system (ABS) prevents a vehicle’s wheels from locking up on dry, wet, or gravel surfaces and helps avoid skidding and loss of control.

Automated Parking:

A newer technology for cars that makes use of onboard front and rear cameras and external sensors to ‘see and feel’ the car into parking spots—especially parallel parking spaces.


An automatic transmission does your car’s shifting so you don’t have to. In general, a vehicle transmission works to efficiently transfer your engine’s power to the wheels in the proper amounts, at the appropriate time. A transmission that contains gears (modern automatics can have eight gears or more) that change according to your driving style and road conditions is considered “automatic.”


The internal skeleton of a vehicle; the underpart of a motor vehicle, or the frame that supports the vehicle’s body and internal systems.

Cruise control: 

Automatically controls the speed of a vehicle to the setting made by the driver; most often used on the highway over longer distances.


Located inside an engine, this is the space in which a piston moves. Engines with more cylinders tend to produce more power, and engines with fewer cylinders tend to deliver greater fuel economy. They are either arranged in a line (“inline”) or a V layout (V6, V8). Some engine layouts, such as those in some Subarus, even have their cylinders arranged in a horizontally-opposed fashion. 

Drive (2WD, 4WD, All-Wheel Drive): 

“Drive” refers to the wheels that are driven by a vehicle’s engine. In a two wheel drive car or truck, the engine’s power is routed to either the front or rear set of wheels. Four-wheel-drive vehicles have their front and rear wheel sets powered at the same time. You “switch on” most 4wd systems yourself. All-wheel-drive systems use sensors to determine which wheels get the most power to handle road conditions.

Flex Fuel Vehicle:

Any car or truck with an engine adjusted to burn fuel that’s either 100 percent gasoline, or gasoline plus ethanol of varying percentages. Available in the US since the late 1990s, flex-fuel cars and trucks are also known as E85 vehicles.


Horsepower refers to a unit of work done over time; one horsepower is equivalent to 746 watts, or 33,000 foot-pounds, of work per minute; The concept was defined in the 1700s by James Watt, a Scottish engineer, when he was working with horses and wanted to be able to refer specifically to their power.


Also known as a stickshift, a manual transmission lets you select the gears yourself, as you’re driving. Older cars had four or even three gears to choose from; today’s manual transmissions offer five, six, or seven gears. These transmissions require more driver involvement below the dashboard as well: there’s a third pedal, or “clutch” that the driver pushes to facilitate gear shifts.


Amount of miles one can drive per gallon of gas expended. Typically, cars can drive more miles per gallon on the highway; city driving returns fewer miles per gallon due to more frequent stops and starts.


A supercharger is a pump that sits on top of or near an engine and works to push a highly-compressed mix of fuel and air into the combustion chambers and give you more horsepower.


A twisting force that causes or tends to cause rotation. Initiates the movement of a stationary vehicle.

Towing capacity: 

The maximum amount of weight a vehicle can pull behind it (not including onboard passengers and cargo).

Traction Control:

When your car pushes varying amounts of power to your drive wheels based on road conditions, you’ve got a vehicle that’s equipped with traction control. Traction control is often included as part of your car's electronic stability control (ESC) system. When one of your car's tires begins to slip or overspin, the traction control system applies the brake to only that wheel. As the wheel slows, your tire is able to regain a grip on the road so you can maintain control of the car. In some vehicles, these systems also reduce engine power to help correct traction loss.


Attached to an engine, the transmission is a series of gears that translate the engine’s output into usable power at the driven wheels, at the time it’s needed.


An add-on for smaller, high-compression engines that uses a vehicle’s exhaust gases to force more air/fuel mixture into the engine’s combustion chamber, giving you more power when you need it. Read more about turbochargers here.

Vehicle Transfer:

If the right used car for you isn’t at the CarMax location closest to you, there’s a good chance we can bring it to your town. Vehicle transfer is available with thousands of cars in our inventory (excluding new cars, Certified Used cars from our Laurel Toyota or Kenosha, WI, locations, and cars identified as non-transferable). CarMax has transferred over one million cars between more than 160 locations. Local transfers are free, and take about three days; non-local transfers will take more time and fee may apply.

* Price excludes taxes, title, registration, and fees. Applicable transfer fees are due in advance of vehicle delivery and are separate from sales transactions.

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