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 HazMatmateriais perigosos
- Substances that endanger health, safety or property when transported.
- tirespneu
- The rubber casings on the wheels that grip the road.
- commercial driver's license CDLCDL (carteira de motorista comercial)
- A commercial driver's license (CDL) is required to drive a commercial motor vehicle (CMV).
- tractorcavalo mecânico
- The power unit built to pull a semitrailer on its fifth wheel.
- placardplacas de advertência
- A diamond-shaped sign on a vehicle showing its cargo's hazard class.
- skidderrapagem
- The tires lose their grip and the vehicle slides.
- commercial motor vehicle CMVveículo motorizado comercial
- A commercial motor vehicle (CMV) is a heavy truck, big bus, or placarded vehicle.
- warning devicestriângulos de segurança
- Reflective triangles or flares that warn traffic your vehicle is stopped.
- brake pedalpedal do freio
- The foot control that sends air to the brakes.
- mirrorsespelho lateral
- Side-mounted glass showing the driver traffic beside and behind the vehicle.
- parking brakefreio de estacionamento
- The brake that holds the vehicle still when parked.
- tractiontração
- 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
A to Z
0–9
A
B
C
- cargo doors
- cargo securement
- catwalk
- center of gravity
- Class A
- Class B
- Class C
- clutch pedal
- combination vehicle
- commercial driver's license
- commercial learner's permit
- commercial motor vehicle
- compressor belt
- control arm
- controlled braking
- converter dolly
- convex mirror
- countersteering
- coupling
- cruise control
- curve speed
- cut-in pressure
- cut-out pressure
D
- danger zone
- deadhead
- dedicated route
- detention
- disc brakes
- dispatcher
- disqualification
- distracted driving
- divided highway
- door ties
- DOT
- DOT bumper
- DOT physical
- doubles
- doubles/triples endorsement
- downgrade
- drag link
- drain valve
- drive axle
- drive shaft
- drive-wheel skid
- driver vehicle inspection report
- drop and hook
- Drug and Alcohol Clearinghouse
- dry van
- dual air brake system
- dual tire spacing
- DUI
E
F
G
H
L
P
R
S
- S-cam
- safe speed
- safety valve
- school bus
- school bus endorsement
- seat belt
- semitrailer
- service brake
- service line
- shifter
- shipper
- shipping paper
- shock absorber
- shoulder
- skid
- skid plate
- skills test
- slack adjuster
- sleeper berth
- sliding fifth wheel
- sliding tandem
- smooth bore
- spare fuses
- speed limit
- splash guards
- spring brake pop-out range
- spring brake pop-out test
- spring brakes
- spring mounts
- stab braking
- standee line
- static air leak test
- steering gear box
- steering linkage
- steering wheel play
- steps
- stopping distance
- suspension
T
- tailgating
- tandem axles
- tank and hazmat endorsement
- tank vehicle
- tank vehicle endorsement
- tarp
- team driving
- tie rod
- tie-downs
- tire blowout
- tires
- torsion bar
- total stopping distance
- traction
- tractor
- tractor protection valve
- traffic violation
- trailer air supply control
- trailer hand valve
- training provider registry
- tread depth
- tread depth minimums
- triples
- tug test
- turn signals
- two-lane road
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