What does alcolock mean?
An alcolock is a safety device installed in a vehicle to prevent driving under the influence of alcohol. Before the engine will start, the driver must breathe into a built-in analyser; if the measured blood alcohol concentration exceeds a preset limit, the ignition remains locked. Also known as an alcohol interlock or ignition interlock device, the alcolock is widely used both as a court-ordered condition following drink-driving convictions and voluntarily by commercial fleets seeking to enforce sobriety among drivers. Many jurisdictions run formal alcolock programmes in which offenders regain their licences earlier in exchange for fitting the device, sometimes paired with regular data logging and servicing. The word combines 'alcohol' with 'lock', reflecting its function of literally locking out intoxicated drivers. As a term, it belongs firmly to the domains of road safety, transport regulation, and automotive technology rather than everyday conversation, but it has become increasingly familiar as governments expand its use in efforts to reduce alcohol-related road deaths.
nounAn alcolock is a breath-analysis device fitted to a vehicle that prevents the engine from starting if the driver's blood alcohol concentration exceeds a preset limit. It is also known more generically as an alcohol interlock or ignition interlock device.
- A vehicle-mounted breath-analysis device connected to the ignition system that prevents the engine from starting when the driver's measured blood alcohol concentration exceeds a set threshold.
"After his second drink-driving conviction, the court required him to have an alcolock installed in his car."
"Drivers convicted of repeat drink-driving offences may be ordered to fit an alcolock as a condition of getting their licence back."
"The commercial fleet equipped all its lorries with alcolocks to guarantee that no driver could start a vehicle while over the limit."
The plural is standard and typically appears when discussing fleets or programmes that equip multiple vehicles.
"The taxi company fitted alcolocks to its entire fleet last year."
Blow before you go: an alcolock makes your car refuse to start unless you prove you're sober.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of alcolock
The word alcolock is a modern compound formed from 'alcohol' and 'lock', mirroring the device's function of locking a vehicle's ignition against drunk drivers. The element 'alcohol' ultimately derives from Arabic al-kuḥl, originally referring to powdered antimony used as eye cosmetic, which entered European scientific vocabulary via medieval Latin. The device itself emerged in the late twentieth century alongside the development of breath-analysis technology, and the term gained currency through European road-safety programmes, where it is often used interchangeably with the broader terms 'alcohol interlock' and 'ignition interlock device'.
How alcolock is actually used
The term is used chiefly in road-safety, legal, and motoring contexts, particularly in Europe and North America. In North American usage the equivalent term 'ignition interlock' or 'alcohol interlock' is often preferred, and legislation frequently refers to the device generically rather than by the branded word 'alcolock'. The word carries no strong connotation beyond its technical association with drink-driving prevention.
Easily confused with alcolock
Alcohol is the intoxicating substance itself, whereas an alcolock is a mechanical device that measures it and blocks the vehicle from starting.
A breathalyser is a handheld testing instrument used by police or individuals to measure blood alcohol; an alcolock is permanently wired into a vehicle's ignition system and physically prevents starting.