CDL glossary

The words the CDL knowledge tests use, with a short meaning and how the test asks about them.

This page is in English. Where a word has a checked translation, it appears after the English term.

Most tested words

hazardous materials HazMat
materiais perigosos
Substances that endanger health, safety or property when transported.
tires
pneu
The rubber casings on the wheels that grip the road.
commercial driver's license CDL
CDL (carteira de motorista comercial)
A commercial driver's license (CDL) is required to drive a commercial motor vehicle (CMV).
tractor
cavalo mecânico
The power unit built to pull a semitrailer on its fifth wheel.
placard
placas de advertência
A diamond-shaped sign on a vehicle showing its cargo's hazard class.
skid
derrapagem
The tires lose their grip and the vehicle slides.
commercial motor vehicle CMV
veículo motorizado comercial
A commercial motor vehicle (CMV) is a heavy truck, big bus, or placarded vehicle.
warning devices
triângulos de segurança
Reflective triangles or flares that warn traffic your vehicle is stopped.
brake pedal
pedal do freio
The foot control that sends air to the brakes.
mirrors
espelho lateral
Side-mounted glass showing the driver traffic beside and behind the vehicle.
parking brake
freio de estacionamento
The brake that holds the vehicle still when parked.
traction
tração
The grip between the tires and the road surface.

Topics

  • Air brakesFreios a ar

    Air brakes stop a heavy vehicle with compressed air instead of brake fluid.

    brake pedal, parking brake, air brakes

  • Combination vehicles, doubles and triplesVeículos combinados, reboques duplos e triplos

    A combination is a tractor or truck pulling one or more trailers.

    tractor, jackknife, triples

  • Hazardous materialsMateriais perigosos

    Hazardous materials are cargo that can harm people or property if it spills, burns or leaks.

    hazardous materials, placard, shipping paper

  • Tank vehiclesVeículos-tanque

    A tank vehicle carries liquid or gas in bulk.

    tank vehicle, center of gravity, liquid surge

  • Passenger and school busVeículos de passageiros e ônibus escolares

    These words come from the Passenger and School Bus tests: loading and unloading, emergency exits, railroad crossings and the danger zone around a bus.

    railroad crossing, school bus, emergency exit

  • Pre-trip inspection partsPeças da inspeção pré-viagem

    These are the parts you name and check during the pre-trip inspection test.

    tires, warning devices, mirrors

  • Driving and safetyDireção e segurança

    Words from the General Knowledge test about controlling the vehicle: stopping distance, skids, following distance, securing cargo, and the limits on speed, alcohol and fatigue.

    skid, traction, stopping distance

  • License, rules and roadsideCDL, regras e inspeções rodoviárias

    Who needs a CDL, which class, which endorsements and restrictions, and the rules that follow you on the road: hours of service, medical cards, inspections and disqualification.

    commercial driver's license, commercial motor vehicle, pre-trip inspection

  • Numbers and units on the testNúmeros e unidades no exame

    The test uses US units: feet, miles per hour, psi, pounds and gallons.

    feet, miles per hour, miles

  • Work and freight wordsPalavras de trabalho e frete

    Words you hear from dispatchers, brokers and shippers in your first weeks.

    shipper, flatbed, dispatcher

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