ki·nase \ˈkīˌnās, ˈkiˌ-\noun (-s) Etymology: International Scientific Vocabulary kinetic + -ase; originally formed in German 1.: a substance (as enterokinase) that converts a zymogen into an enzyme — compare coenzyme 2.: any of various enzymes (as hexokinases) that promote phosphorylation processes < adenylic kinase or myosine catalyzes the transfer of phosphate groups among the adenosine phosphates > — compare phosphorylase