Bioethanol is a fuel made from plants — often sugar cane, corn, or other crops with a lot of sugar or starch — and then mixed with petrol so cars can burn it. It is a kind of alcohol, the same family of chemical as the alcohol in drinks, but you are not meant to drink this; it is for engines. Some countries put a little in ordinary petrol; you may not even notice it at the pump. Though actually, people argue about it: it can mean less oil from under the ground, but growing the crop can use a lot of land that might have grown food. It is a technical word from news, science, and government talk, not a word friends throw around. Biofuel is the bigger umbrella; bioethanol is one liquid kind that mixes with petrol.

生質乙醇。台灣也常說「生質酒精」；中國大陸較多寫「生物乙醇」。