The acetyl radical is a chemical compound consisting of a carbon atom, two oxygen atoms, and a single hydrogen atom. This compound is often used in organic chemistry as a building block for larger molecules. Synonyms for the acetyl radical include acetylide, acetyl group, and acetylonium ion. These terms are often used interchangeably and refer to the same basic compound. Other related terms include acetylcholine, which is a neurotransmitter that contains the acetyl group, and acetylation, which is the process of introducing an acetyl group into a molecule. While the terminology can be complex, the acetyl radical is an essential component in many chemical reactions and plays an important role in many fields of science.