Glossary

Abreast
Side by side
Acceleration
Speeding up
Arrhythmia
Irregular or abnormal heart beat
Axle
A pin, pole, or bar that connects a pair of opposite wheels on a vehicle
Binocular vision
Vision with both eyes
Blind spot
An area that a driver or other road user cannot see directly or with their mirrors This requires them to turn or look sideways to see other road users
Blow out
Sudden tyre failure
Build outs
Kerbing which extends from the side of the road to reduce traffic speed
Cardiovascular diseases
Diseases involving the heart and blood system
Central median island
An area in the centre of a road which separates approaching flows of traffic or a pedestrian crossing
Central nervous system
Brain and spinal cord
Cerebrovascular diseases
Diseases involving blood vessels in the brain
Certificate of Professional Competency (CPC)
A certificate drivers must have before they can drive a HGV or a bus for a living
Chicane
A traffic-calming measure to make vehicles slow down and weave between traffic lanes
Congenital myotonic disorders
Disorders from birth that make it difficult for person to relax their muscles after contracting them
Chevron board
Traffic warning signs with hatch-markings indicating a sudden change in direction
Cross-ply tyres
Tyres with cords made of steel and other materials, which cross at various angles to strengthen the side of the tyre and its tread
Deceleration
Slowing down
Defects
Faults, such as broken mirrors, missing lighting
Design Gross Vehicle Weight (DGVW)
The manufacturers specifications of Gross Vehicle Weight (GVW see below)
Diplopia
Double vision
Diverging
Moving apart. For example, traffic taking a right turn when other traffic is moving straight ahead or traffic leaving a motorway
Fixed wheel bicycle
A bicycle you can back-pedal to brake. It has one wheel which cannot rotate independently of the pedals
Gantries
Overhead steel structures across carriageways to hold up signs
Garda Siochana
Irelands national police service
Ghost island
A marked area on the road that shows where a motorway and a slip road meet
Graduating
Moving from one stage to the next
Gross vehicle weight (GVW)
The weight of a vehicle together with the maximum load it is designed to carry
Hard shoulder
A part of the road that is divided by broken or continous yellow lines from the rest of the road and should be used only by certain road users in certain situations
Hatched marking
Chevron markings on the road which help separate traffic lanes
Hazard
Anything that could be a source of danger on the road
Intoxicant
Something that can affect a persons behaviour, perception, mood or alertness
Invalid-carriages
Vehicles specially designed or constructed for people with disabilities. This does not apply to conventional motor cars which are specially adapted for disabled persons and which are permitted to use a motorway
National road
A major road linking urban areas and consisting of motorway roads identified by route numbers, for example M1, and other routes identified by oute numbers, for example N11
Land tractor
Commonly called al tractor, these vehicles are designed to work on land in connection with agricultural, forestry or land drainage-type operations and are driven on a public road only when proceeding to or from the site of such work
Lighting-up hours
The period commencing one half-hour after sunset on any day and expiring one half-hour before sunrise on the next day.
Luas
The tram system operating in Dublin city and suburbs
Manoeuvre
Any action to steer or change the course of a vehicle, such as moving off, changing lanes, leaving a roundabout, turning left or right, taking U-turns or reversing
Median space
A gap provided in the centre of a dual carriageway to allow vehicles to cross through or turn onto another road
Merging
Coming together. For example, traffic entering a motorway from a slip road and joining other traffic
Moped
A light motorcycle of 50cc or less that has a maximum speed of 45km/h
Motorcycle engine capacity
Cubic capacity or CC of engine
Motorcycle power rating
Engine power output
Muscular atrophy
Wasting of muscles
Nearside
Left-hand side
Negligence
Failing to act with reasonable care
Night-driving mode (mirror)
Darkened reflection which reduces dazzle
Non-national road
A local or regional road linking villages and towns within a county or district identified by an R or L number sign
Offside
Right-hand side
Ophthalmic optician
An optician qualified to prescribe glasses and contact lenses and detect eye diseases
Outer lane
The lane nearest the centre of the road in a dual carriageway or two- or three-lane motorway
Paraplegia
Loss of movement in both legs
Peripheral nervous system
Nerves in the body outside the brain and spinal cord
Permit
A legal document giving permission to do something like park in a particular place or use certain roads
Pinch points
Traffic calming measure where sections of the road are narrowed to reduce speed
Pointsman
A Garda who controls the flow of traffic
Prescription
A written note from a doctor or hospital stating what medicines a person should take and when they should take them
Professional drivers
Drivers whose main income is from driving, such as bus, coach and haulage drivers
Psychotropic
Chemical substance that affects the mind, leading to changes in emotions, behaviour, alertness and perception
Radial tyres (radial ply tyres)
Tyres with cords made of steel and other materials, which run around under the treads to strengthen them and make them last longer
Retarder
A device that reduces the speed of the vehicle without using the brakes
Safe headway
A safe distance between two vehicles on the road
Sam Browne
A wide strap, made of reflective material, worn around the waist with a strap diagonally over the right shoulder
Secondary controls
Devices in a vehicle that do not direct its movement or braking but control how the driver sees out of the vehicle and how the vehicle is seen; examples are de-misters, windscreen wipers, washers and hazard lights
Single lane (for shuttle working)
Control of traffic through road works one-way system where manual operated stop/go signs are in use
Stationary
Stopped, for example in a line of traffic, at a stop light or in a parking space
Swan neck
The course followed by a vehicle when the driver passes the correct point for taking a right turn and needs to make a bigger effort to correct the position when completing the turn
Tabard
Sleeveless yellow fluorescent vest worn by motorcyclists with 'L' plates clearly displayed to front and rear.
Tachograph
A device that measures and records the speed, distance and time travelled by a vehicle
Tailgating
Driving too close to a vehicle in front
Tarpaulin
Waterproof canvas material used to cover cargo being transported
T-junction
A junction where the meeting of a minor road with a major road forms a 'T' Shape
Tread (tyres)
The grooves on a type which provide a grip on the road
Variable message sign
An upright electronic sign, whose content changes to inform on roads and road safety
Vigilant
Careful, watchful, looking out for possible danger
Work vehicles
Vehicles used at sites or roadworks that usually do not drive on the road
Yield
Give way to other road users