phosphorylase Syllabification: (phos·pho·ryl·ase)Pronunciation: /ˈfäsfərəˌlās, fäsˈfôrəˌlās/Definition of phosphorylase noun Biochemistry an enzyme that introduces a phosphate group into an organic molecule, notably glucose. phosphorylase in other Oxford dictionaries Definition of phosphorylase in the British & World English dictionary