CDL Glossary

The world of commercial driving consists of a lot of acronyms and technical jargon. If you're a new commercial driver, here is a glossary of commonly used terms that may help you navigate your way.

CDL Terms A-D

Air Brake

Common on some commercial vehicles, an air brake uses compressed air to stop heavy vehicles.

Anti-Lock Breaking System (ABS)

An anti-lock braking system (ABS) is used on many commercial vehicles to control the braking force when hauling large loads. These braking systems are especially helpful during adverse weather conditions, when heavy braking on wet or slick surfaces could cause wheel lockup.

In an ABS, speed sensors are able to detect whether any of the wheels are in danger of locking up as the driver brakes the vehicle. A hydraulic system then counters that locking wheel, which helps prevent the truck from skidding across the road.


A carrier is the person or company whose business is responsible for transporting goods from one place to another.


This acronym stands for commercial driver's license. A CDL is required by the federal government to operate commercial motor vehicles such as:

  • A tractor trailer.
  • A city bus.
  • Most construction vehicles.
  • Vehicles hauling hazardous materials.

CDL Restrictions

A restriction placed on a CDL will prevent a commercial driver from operating a type of vehicle typically associated with his or her class of a license. Visit our guide to CDL Endorsements and Restrictions for details.

Class A CDL

A Class A CDL is required to operate any combination of vehicles that weigh(s) 26,001 lbs. or more, TO INCLUDE a towed vehicle that has a GVWR OVER 10,000 lbs. Common vehicles that may require this class of license include:

  • Tractor trailers.
  • Tankers.
  • Flatbeds.

Class B CDL

A Class B CDL is required to operate:

  • A single vehicle that has a GVWR of AT LEAST 26,001 lbs.
  • The above classified vehicle towing another vehicle with a GVWR of UP TO 10,000 lbs.

Common vehicles that may require this class of CDL include:

  • Straight trucks.
  • Large buses.
  • Construction vehicles.

Class C CDL

A Class C commercial driver's license is required when operating a commercial motor vehicle:

  • Not defined by Class A or B requirements, AND:
    • Is hauling hazardous materials.
    • Is transporting at least 16 passengers (to include you, the driver).


CLP stands for “ commercial learner's permit." A CLP is a requirement for all drivers who intend to operate a commercial motor vehicle. To obtain a CLP, you must take a written examination given by your state's DMV. After completion of the CLP requirements, you may apply for your commercial driver's license (CDL).


CMV stands for “commercial motor vehicle." This is basically another way of referring to the car or truck you are driving for your job.

Combination Vehicle

A vehicle is considered to be a “combination vehicle" when one or more vehicles is being towed by a larger one. Tractor trailers, double trailers, and triple trailers are considered combination vehicles.

Company-Sponsored Training

Some CDL training schools are owned by a trucking company. Instead of paying tuition, company-sponsored training will often train potential drivers for little or no money in exchange for a commitment to work for the company for a specified amount of time.


This acronym stands for compliance, safety, and accountability, and is an initiative created by the Federal Motor Carrier Safety Administration (FMCSA) to improve safety of commercial motor vehicles.


The Department of Transportation (DOT) is the executive branch of the U.S. government responsible for regulation of air, road, and railroad safety. State and federal DOT officers are in charge of the enforcement of all laws and regulations associated with commercial vehicles.


When a tractor pulls two trailers at the same time, it is commonly referred to as a double.

Driver Trainer

After a student graduates from school or has received his or her CDL, additional on-the-job training will often be required. A driver trainer is an experienced driver who instructs new drivers in the first few weeks after joining the company.

CDL Terms E-L


An endorsement on a CDL allows the driver to operate certain types of vehicles. A few examples of vehicles required a CDL endorsement include:

  • Passenger vehicles (P endorsement).
  • Hazmat vehicles (H endorsement).
  • School bus (S endorsement).
  • Tankers (N endorsement).

For more information, please visit our page on CDL endorsements and restrictions.


The Federal Motor Carrier Safety Administration (FMCSA) is a division within the Department of Transportation that helps to create safety measures for commercial motor vehicles.


GCVWR stands for “ gross combined vehicle weight rating." This is the maximum weight allowed to be transported by one vehicle inclusive of another (truck and trailer) according to the manufacturer.


The gross combined weight rating (GCWR) refers to the combined weight of a vehicle and its trailers.


The maximum allowable operating weight for a vehicle according to its manufacturer is known as the gross vehicle weight rating (GVWR).


HAZMAT is short for hazardous materials—these are defined by the federal government as potentially dangerous cargo, and may include:

  • Explosives.
  • Gases.
  • Flammable and combustible liquids.

To operate a commercial vehicle with hazardous materials, you must have a hazmat endorsement.

Interstate Commerce

Interstate commerce is the transportation of goods across state lines. Interstate commerce is regulated by the federal government.

Intrastate Commerce

Intrastate commerce is the transportation of goods within your state of license only. Rules and regulations for intrastate commerce may differ from interstate commerce depending on the state.


The goods being pulled by the driver in a commercial motor vehicle are sometimes referred to as the load.

CDL Terms M-Z


A Motor Vehicle Report (MVR) is often used by trucking companies to determine the driving history and hiring eligibility of potential employees. MVRs are also commonly called “driving records." Visit our section on Employee Driving Records for more details.

OTR Driver

This stands for over-the-road driver, and typically refers to the transportation of goods over long distances. On OTR trips, drivers may be away from home for several weeks at a time and often sleep inside the truck's cab.


A driver is the owner-operator if he or she owns the tractor or other commercial vehicle being used to transport goods.


A pre-hire is a trucking student who is hired under certain conditions before he or she graduates. A pre-hire statement will usually guarantee:

  • A student meets basic hiring requirements.
  • Upon graduation, the student may attend a company's orientation to see if he or she meets other requirements before the hiring process is complete.


PrePass is the commercial equivalent of EZpass; basically, it allows commercial vehicles to bypass weigh stations using an automatic vehicle identification (AVI) system that recognizes your vehicle. Vehicles must be pre-certified for this service. Visit the PrePass website for details.

Pre-trip Inspection

A pre-trip inspection ensures proper and safe functioning of all equipment; this includes, but is not limited to:

  • Headlights and brake lights.
  • Windshield.
  • Mirrors.
  • Grill.
  • Hood.


The Professional Truck Driver's Institute (PTDI) is an organization which provides certifications to training schools and programs.

Regional Run

A regional run occurs when a driver's routes are kept within a certain region, such as New England or the Pacific Northwest.


A route is the chosen mapped course a driver or company takes to deliver goods from one location to another.

Straight Truck

A straight truck is a single vehicle without a hitch attachment like those used with a tractor trailer. A straight truck will usually have a cargo area (if any) attached directly to the chassis.


A truck designed to transport heavy loads by pulling an attached trailer.

Tractor Trailer

Consists of a tractor (truck) and one or multiple trailers.

DMV.ORG BBB Business Review