Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros (κηρός wax). The word "Kerosene" was registered as a trademark by Abraham Gesner in 1854, and for several years, only the North American Gas Light Company and the Downer Company (to which Gesner had granted the right) were allowed to call their lamp oil "Kerosene". It eventually became a genericized trademark.

In the United Kingdom, two grades of heating oil use this name - premium kerosene (more commonly known in the UK as paraffin) BS2869 Class C1, the lightest grade, which is usually used for lanterns, wick heaters, and combustion engines; and standard kerosene BS2869 Class C2, a heavier distillate, which is used as domestic heating oil. Premium Kerosene is usually sold in 5 or 20 litre containers from hardware, camping and garden stores and is often dyed purple. Standard kerosene is usually dispensed in bulk by a tanker and is colourless.

Kerosene is usually called paraffin (sometimes paraffin oil) in Southeast Asia and South Africa (not to be confused with the much more viscous paraffin oil used as a laxative, or the waxy solid also called paraffin wax or just paraffin); variants of petroleum in parts of Central Europe (not to be confused with crude oil to which it refers in English); the term "kerosene" is usual in much of Canada, the United States, Australia (where it is usually referred to colloquially as "kero") and New Zealand.

Kerosene is widely used to power jet-engined aircraft (jet fuel) and some rockets, but is also commonly used as a heating fuel and for fire toys such as poi. In parts of Asia, where the price of kerosene is subsidized, it fuels outboard motors rigged on small fishing craft.

Kerosene is typically (and in some jurisdictions legally required to be) stored in a blue container to avoid its getting confused with the much more flammable gasoline, which is typically kept in a red container. Diesel fuel is generally stored in yellow containers for the same reason.
