glycerol UK /ˈɡlɪs.ə.rɒl/US /ˈɡlɪs.ə.rɔl/ noun2 •1,2,3-trihydroxy-propane or propan-1,2,3-triol; a trihydric alcohol •A syrupy sweet liquid obtained as a by-product in the manufacture of soap from animal or vegetable oils and fats; it is used as an antifreeze, a plasticizer, and a food sweetener and in the manufacture of dynamite, cosmetics etc. formsglycerols