Commonly referred to simply as alcohol or spirits, ethanol is also called ethyl alcohol. It is a psychoactive drug and one of the oldest recreational drugs used by humans. It can cause alcohol intoxication when consumed in sufficient quantity. Beyond being consumed, it is used as a solvent, as an antiseptic, as a fuel and as the active fluid in modern (post-mercury) thermometers. It is a volatile, flammable, colorless liquid with the structural formula CH3CH2OH, often abbreviated as C2H5OH.

Ethanol is the systematic name defined by the International Union of Pure and Applied Chemistry (IUPAC) for a molecule with two carbon atoms having a single bond between them ,and an attached functional group-OH group.

The name ethanol was coined as a result of a resolution that was adopted at the International Conference on Chemical Nomenclature that was held in April 1892 in Geneva, Switzerland.