Acetyl \Ac"e*tyl\, n. [L. acetum vinegar + Gr. ? substance. See {-yl}.] (Chem.) A complex, hypothetical radical, composed of two parts of carbon to three of hydrogen and one of oxygen. Its hydroxide is acetic acid.
acetyl n : the organic group of acetic acid (CH3CO-) [syn: {acetyl group}, {acetyl radical}, {ethanoyl group}, {ethanoyl radical}]