Trucking Terms Glossary

glossary page

Do you know what a Bobtail is? Ever wonder what BOL stands for? Here is a Trucking Terms Glossary authored by the American Trucking Association (ATA). It isn't an exhaustive list, but it is a great starting point for anyone unfamiliar with the trucking industry.

ABS (Anti-lock Braking System) – Computer, sensors and solenoid valves which together monitor wheel speed and modulate braking force if wheel lockup is sensed during braking. Helps the driver retain control of the vehicle during
heavy braking on slippery roads.

Air Ride Suspension – Suspension which supports the load on air-filled rubber bags rather than steel springs. Compressed air is supplied by the same engine-driven air compressor and reservoir tanks which provide air to the air brake system.

Anchor It – Apply brakes for an emergency stop. Bill of Lading – Itemized list of goods contained in a shipment.

Blind Spot – Areas around a commercial vehicle that are not visible to the driver either through the windshield, side windows or mirrors.

Bobtail –Tractor operating without a trailer. Also refers to straight trucks.

CargoWeight – Combined weight of all loads, gear, and supplies on a vehicle.

Cartage Company – A Company that provides local (within a town, city, or municipality) pick-up and delivery.

CDL (Commercial Driver’s License) – A license that authorizes an individual to operate commercial motor vehicles and buses over 26,000 pounds gross vehicle weight.

Container – Standard-sized rectangular box used to transport freight by ship, rail, and highway.

Converter Dolly – Auxiliary axle assembly equipped with a fifth wheel (coupling device), towed by a semitrailer and supporting the front of, and towing, another semitrailer.

Doubles (Twins, Twin Trailers) – Combination of a tractor and two semitrailers connected in tandem by a converter dolly.

EOBR (Electric On-Board Recorder) – Cab-mounted device that electronically records data such as truck speed, engine rpm, idle time, and other information useful to trucking management.

Exempt Carrier – A company that transports commodities exempted from Interstate Commerce Commission economic regulation.


For-Hire Carrier – Company in the business of transporting freight belonging to others.

Hazmat – Hazardous materials, as classified by the U.S. Environmental Protection Agency. The transport of hazardous materials is strictly regulated by the U.S. Department of Transportation.

Hours-of-Service – U.S. Department of Transportation safety regulations that govern the hours of service of commercial vehicle drivers engaged in interstate trucking operations.

Intermodal Transportation –The transportation movement involving more than one mode (e.g., rail/motor, motor/air, rail/water).

JIT (Just-In-Time) – Manufacturing system which depends on frequent, small deliveries of parts and supplies to keep on-site inventory to a minimum.

Landing Gear – Retractable legs that support the front of a semitrailer when it's not coupled to a trailer.

LCV (Long Combination Vehicle) – In general, vehicles that are longer than standard doubles rigs. Examples of LCVs that are permitted in some U.S. western states and eastern toll roads are twin 48-foot trailers and triple 28-foot trailers.

Logbook – Book carried by truck drivers in which they record their hours of service and duty status for each 24-hour period. Required for interstate commercial trucking by the U.S. Department of Transportation.

Line-haul Driver –Truck driver who travels a set route from city to city and typically returns home after each shift. Also known as a regional driver.

Local Driver –A truck driver who picks up and delivers packages along a city route. Drivers typically run the same route every day, returning home after each shift. Also known as a city or P&D driver.

LTL (Less-Than-Truckload) – A quantity of freight less than that required for the application of truckload (TL) rate; usually less than 10,000 pounds.

LTL Carrier –Trucking company that consolidates less-than-truckload cargo for multiple destinations on one vehicle.

Owner-Operator –A truck driver who owns and operates his own truck.

Over-the-Road Driver –Truck driver who travels cross-country to deliver freight and usually sleeps within a berth in the truck cab. Typically averages over 100,000 miles per year.

P&D – Pickup and delivery. May also be referred to as a city driver.

Payload –Weight of the cargo being hauled.

Peddle Run –Truck route with frequent delivery stops.

Private Carrier – A business that operates trucks primarily for the purpose of transporting its own products and raw materials. The principal business activity of a private carrier is not transportation.

Professional Truck Driver – Different categories of drivers include over-the-road, line-haul, and local.

Reefer – Refrigerated trailer with insulated walls and a self-powered refrigeration unit. Most commonly used for transporting food. 

Semitrailer –Truck trailer supported at the rear by its own wheels and at the front by a fifth wheel mounted to a tractor or a dolly.

Sleeper – Sleeping compartment mounted behind a truck cab, sometimes attached to the cab or even designed to be an integral part of it.

Sliding Fifth Wheel – The fifth wheel is mounted to a mechanism that allows it to be moved back and forth for the purpose of adjusting the distribution of weight on the tractor’s axles.

Straight Truck – A vehicle that carries cargo in a body mounted to its chassis, rather than on a trailer towed by a vehicle.

TL (Truckload) – The quantity of freight required to fill a trailer; usually more than 10,000 pounds.

TL Carrier –Trucking company that dedicates trailers to a single shipper’s cargo, as opposed to an LTL (Less Than Truckload) carrier which transports the consolidated cargo of several shippers and makes multiple deliveries.

Tractor –A truck designed primarily to pull a semitrailer by means of a fifth wheel mounted over the rear axle.

Tractor Trailer –Tractor and semitrailer combination.

Tri-Axle –Truck, tractor, or trailer with three axles grouped together at the rear.

Trip Leasing – Leasing a company’s vehicle to another transportation provider for a single trip.

Click for your own printable copy of the ATA glossary. You can also learn these terms first-hand by joining Buchanan's Best or by bringing your freight to us to handle.