Condensation polymers of ethylene oxide and water, of the general formula HO(CH2CH2O)nH, where n equals the average number of oxyethylene groups (300–6,000); they vary in consistency based on molecular size; PEG 300 is a viscous liquid; PEG 6000 is a waxlike solid; PEGs are soluble in water and are used as pharmaceutic aids.
Medical dictionary. 2011.