proteoglycan

A subclass of protein in which the carbohydrate units are polysaccharides that contain amino sugars. The protein is glycosylated by one or more (up to about 100) glycosaminoglycans [linear polymers of up to about 200 repeating disaccharide units that consist of a hexosamine (d-glucosamine or d-galactosamine) alternating with a uronic acid (d-glucuronic or l-iduronic) or a neutral sugar (d-galactose)].
Source:
PAC, 1988, 60, 1389 (Nomenclature of glycoproteins, glycopeptides and peptidoglycans (Recommendations 1985)) on page 1391
White Book, p. 85