Plain-English dictionary
Glossary
17 everyday terms explained simply, no jargon.
A
- Alternator
- The part that charges the battery and powers the electrics while the engine runs.
C
- Coolant
- The fluid that carries heat away from the engine to stop it overheating (also called antifreeze).
D
- Depreciation
- The amount of value a car loses over time — usually fastest in its first few years.
E
- EV
- An electric vehicle, powered by a battery and one or more electric motors instead of fuel.
F
- Fuel economy
- How far a car travels on a set amount of fuel, often shown as MPG or L/100km.
H
- Horsepower
- A common measure of an engine's power output.
- Hybrid
- A car that combines a petrol engine with an electric motor and battery to save fuel.
K
- kWh
- Kilowatt-hour — the unit for an EV battery's size and the energy it stores.
O
- OBD-II
- The standard diagnostic port a scanner plugs into to read a car's fault codes.
- Odometer
- The gauge that shows a car's total distance travelled — key when buying used.
P
- PSI
- Pounds per square inch — the unit for tire pressure, listed in the door jamb or manual.
R
- Regenerative braking
- An EV or hybrid feature that recovers energy while slowing down to recharge the battery.
S
- Serpentine belt
- A single belt that drives several engine accessories, like the alternator and water pump.
- Service history
- The record of maintenance a car has had, which helps prove it's been looked after.
T
- Torque
- The turning force an engine or motor produces, felt most in pulling power and acceleration.
- Tread depth
- How much grip is left on a tire; too little means it's time to replace it.
V
- VIN
- The Vehicle Identification Number — a unique code that identifies a specific car and its history.
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