kinase Syllabification: (ki·nase)Pronunciation: /ˈkīˌnās, ˈkinās/Definition of kinase noun [usually with modifier] Biochemistry an enzyme that catalyzes the transfer of a phosphate group from ATP to a specified molecule. Origin: early 20th century: from Greek kinein 'to move' + -asekinase in other Oxford dictionaries Definition of kinase in the British & World English dictionary