oil (a thick black liquid from under the ground that is used to produce fuel or lubricant): This oil well delivers 200 barrels a day.
fuel (a substance that is burned to provide heat or power): Oil, coal, gas, and wood are different kinds of fuel.
gas (a fossil fuel in the form of a gas, used for heating and cooking): Do you use gas or electricity for cooking?
coal (a hard black substance that is extracted from the ground and burned as fuel): This country is rich in coal mine.
petroleum (the refined products derived from oil, like gasoline, diesel, heating oil, jet fuel, and naphtha): They refined crude oil into various petroleum products.
petrol UK (a light fuel obtained from petroleum and used to supply power to the engine of cars and other vehicles): Petrol ignites very easily.
gasoline US formal (a light fuel obtained from petroleum and used to supply power to the engine of cars and other vehicles): This car runs on unleaded gasoline. (also gas) I ran out of gas on my way home.
diesel (a type of heavy oil used as fuel in diesel engines): Most buses run on diesel.
fossil fuel (a fuel such as gas, coal, or oil, that is formed in the earth from dead plants or animals): Fossil fuels are rapidly running out.
