The glycocalyx is a glycoprotein-polysaccharide covering that surrounds the cell membranes of some bacteria, epithelia and other cells.

Most animal epithelial cells have a fuzz-like coat on the external surface of their plasma membranes. This coating consists of several carbohydrate moieties of membrane glycolipids and glycoproteins, which serve as backbone molecules for support. Generally, the carbohydrate portion of the glycolipids found on the surface of plasma membranes helps these molecules contribute to cell-cell recognition, communication, and intercellular adhesion.