Petroleum, a fluid consisting of a mixture of refined petroleum hydrocarbons, primarily consisting of octane, commonly used as a motor fuel.
"The station attendant pumped petrol into the car's tank to power its engine."
In plain English: Petrol is gasoline, which people put into cars to make them run.
"We need to fill up with petrol before we drive home."
Usage: Use this word to refer specifically to gasoline when speaking in British English or other regions outside North America and South Africa. It is the standard term for car fuel there but should be avoided by American speakers who use "gas" instead.
The word petrol comes from French and Medieval Latin versions that borrowed it directly from Ancient Greek petrélaion, meaning "oil of the rock." This original term combined words for stone and olive-like oil to describe a liquid found in rocks before entering English usage.