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Check out the definitions on this page to learn about some common trucking terminology. Check out our CDL slang & trucker lingo definitions too!

ABS (Anti-lock Braking System)

Anti-lock brake systems or ABS are used in Commercial Vehicles to prevent wheels from locking up. Speed sensors detect and prevent potential lockups from happening during braking to prevent skids.


AFV stands for alternative fuel vehicle, which runs on something other than gasoline or diesel fuel.

Air Brake

Air brakes used compressed air to stop a commercial vehicle. In order to drive a CMV equipped with Air Brakes, you must pass the Air Brakes Knowledge test and pass your skills test in a vehicle equipped with air brakes.

Air Ride Suspension

Air Ride Suspension uses air instead of springs to support the weight of the load.

Anchor It

Means to make an emergency stop.


An auxiliary power unit (APU) allows the drive to use heat, AC, and electricity without running the truck’s engine.

Average Length of Haul

The average distance between pick-up and delivery points for a company’s trips.


A baffle is used to separate sections of a tanker to limit the effects that flowing liquid has on vehicle control.


A sleeping area behind the cab of a truck.

Bill of Lading

List of goods in a shipment.

Blind Spot

Areas around a vehicle that are not visible in the driver’s mirrors.


Bobtail, or deadhead, refers to a tractor truck operating without a trailer.

Bridge Formula

A formula that regulates how much weight can be put on each axel and the distance between each axel.


A strong wall used to either protect the cab from the load or a wall used within a trailer to partition the load.


Sleeping area behind the cab of a truck.

Cargo Weight

The total weight of all load, supplies, and gear on a vehicle.


An individual or company who transports goods from one place to another.

Cartage Company

A company that provides delivery and pick-up services locally.

CAT Scale

A network of truck scales across the U.S. and Canada.


CB (Citizens Band) radio is a two-way radio system that does not require a license to own and operate.

CDL (Commercial Driver’s License)

A driver’s license that allows you to operate commercial motor vehicles and transport certain types of cargo or certain amounts of passengers.

CDL Restrictions

Restrictions placed on a CDL that either prevent a driver from operating certain types of vehicles or require a driver to comply with certain requirements while driving.


The Commercial Driver’s License Information System allows states to cross-reference information about CDL holders.


Code of Federal Regulations

Chassis Weight

The weight of an empty vehicle.


A Commercial Learner’s Permit allows you to practice and learn how to drive a commercial vehicle after passing your written knowledge tests.


CMV stands for commercial motor vehicle.

Combination Vehicle

A vehicle with two parts – i.e. a tractor or cab and a trailer or a series of 2-3 connected trailers.

Common Carrier

A transportation company that provides carrier services to the general public as opposed to a private or dedicated carrier.

Company Sponsored Training

A commercial driver’s license Company Sponsored Training program is a CDL training course offered by a trucking company offered at low-to-zero upfront costs. The program leads to employment and the training is typically paid back with portions of the driver’s paycheck or requires the driver to fulfil a work contract with the company.

Compressed gas

Any gas or liquefied gas that is stored in a container under pressure.


The individual or company that is receiving delivered freight.


A standard shipping container is used to move freight by truck, boat, or rail.

Container Chassis

A shipping trailer designed to carry shipping containers.

Contract Carrier

A company delivers freight for a small number of customers.

Converter Dolly

An auxiliary axle that connects a semi-trailer to a trailer.

Covered Wagon

A flatbed truck with side plates and coverings.


CPM stands for Cents Per Mile or the rate at which drivers are paid per mile driven.


CSA stands for Compliance, Safety, and Accountability. It’s an initiative from the Federal Motor Carrier Administration to improve the safety of commercial vehicles.

Day Cab

A tractor with no sleeping area in the cab.


An empty truck with no cargo or no trailer.

Dedicated Route

A carrier that delivers freight on a regular route and/or customer.


The contact person for the driver to communicate with in regards to scheduling loads, changes, relaying messages, etc.


The Department of Motor Vehicles or its equivalent in each state is responsible for conducting the processing of commercial driver’s license applications.


The Department of Transportation oversees and regulates air, road, and railroad transportation.

Double Clutch

The practice of engaging and disengaging the clutch twice when changing gears in a standard transmission without a synchronizer.


A combination of two trailers.


Moving freight a short distance as part of its longer overall route.

Driver Trainer

A CDL driver trainer is an experienced CDL driver who can instruct or ride-along with newly hired drivers.

Drop and Hook

Refers to a driver dropping one trailer at the destination and hooking up to another.

Drop Yard

A drop yard is a place where truck drivers can park their trucks and trailers.

Dry Freight

Non-liquid freight.

Dry Van

A truck or trailer without refrigeration or special features/requirements.


Electronic Document Interchange can be used to share transportation/freight documents like Bills of Lading electronically.


CDL endorsements allow CDL drivers to operate different types of commercial vehicles to haul certain types of freight.


An Electric On-Board Recorder logs information about a truck’s trip.


Environmental Protection Agency


Federal Aviation Administration


Federal Highway Administration

Fifth Wheel

The fifth wheel is how tractors and trailers connect.


An open/flat trailer.


Federal Motor Carrier Administration is a division within the DOT that regulates commercial vehicles and drivers.

Forced Dispatch

Describes drivers who need to take load and delivery orders from dispatch.

For-Hire Carrier

A company that transports freight for others.


Gross Axle Weight Rating describes how much weight a vehicle’s axle can carry.


Gross Combined Vehicle Weight Rating describes that maximum weight that can be combined and carried by a certain vehicle.


Gross Combined Weight Rating describes the total combined weight of a truck and trailer.


A device that regulates a vehicle’s top speed.


Describes the steepness of angle of a hill or slope.

Gross weight or mass

The weight of a package and its contents.


Gross Vehicle Weight Rating describes the maximum weight of the vehicle and everything it can carry.


HAZMAT stands for hazardous materials as classified by the EPA and regulated by the DOT.

Headache Rack

A block/barrier behind the cab to protect the cab from shifting loads or accidents.


Hours of Service – the FMCSA regulates how long and when drivers can be on duty.

Intermodal Transportation

Transportation of freight using more than one method.


Between more than 1 state. i.e. Across state lines.


Within a single state.


International Registration Plan

Irregular Route Common Carrier

A carrier that will move freight with no set routes.


A situation in which the tractor and trailer are at a sharp angle to one another.


Connects a truck to a trailer.

Kingpin (trailer)

Landing Gear

Supports the trailer when it is not attached to a truck.


A Long Combination Vehicle is longer than a standard double combination vehicle.

Lift Axle

An axle designed to be raised or lowered depending on the weight of the load in order to comply with federal axle weight regulations.

Limited quantity

A maximum amount for a specific material or substance.


Linehaul drivers move freight from one terminal to another, from which local deliveries are made.


The freight that is being moved by the carrier.

Loaded Miles

Distance traveled with a load.

Local Driver

A truck driver who delivers packages on a regular, local route. Also referred to as a P&D.


Where a driver records their service hours and status.


Driving long distances.


A flatbed trailer with a low deck designed for carrying tall or large loads.


Less-Than-Truckload refers to cargo that takes up less than a trailer’s full capacity.

LTL Carrier

A carrier that consolidates multiple LTL shipments into one load.


The person who loads and unloads a truck.


Motor Carrier Permit


A Motor Vehicle Report tracks a driver’s driving record and history of violations, infractions, or accidents.


National Highway Traffic Safety Administration


National Transportation Safety Board


Over the Road refers to long haul and long term trucking.


The amount of allowance for a liquid to expand.


Restricts a driver from operating, usually caused by an infraction.

Owner Operator

A driver who owns the vehicle being used to haul freight.


Pick up and Delivery refers to local truck drivers.


Weight of the cargo.

Peddle Run

Route with frequent stops.

Pintle Hook

A Pintle Hook is used to connect double and triple trailers.

Pre-trip Inspection

An inspection to make sure all equipment and loads are safe.

Private Carrier

A carrier that transports goods for its own company.


Pounds Per Square Inch


Professional Truck Driver’s Institute provides certifications to CDL training programs.


A refrigerated trailer.

Regional Run

A trucking route that stays within a certain region.


Assists the brakes to slow the vehicle.


A trailer designed for both truck and rail travel.


The directions that a truck follows to deliver goods.

Runaway Ramp

Wide, soft areas near steep downhill grades where trucks can pull into to stop if the brakes fail.


A trailer with rear wheels connected to a truck by a fifth wheel or dolly.


A place in the truck’s cab to sleep.

Sliding Fifth Wheel

A fifth wheel that can move depending on load weight.

Step Deck

A flatbed with a lower section that is designed to carry taller or oddly shaped loads.

Straight Truck

A single truck without a trailer attachment. The trailer area and truck share the same chassis.

Tank vehicle

A commercial vehicle with a tank to carry liquid or gas cargo.


A hub facility of carrier companies.


Truckload or full trailer load.

TL Carrier

A carrier that ships a full truckload at a time.


A truck designed to pull a heavy trailer.

Tractor Trailer

A truck and a trailer.


Transportation Security Administration


Vehicle Identification Number

Yard Tractor

A tractor that is used to move trailers around a warehouse, terminal, or distribution center.