ˈenˌzīm noun
( -s )
Etymology: German enzym, from Middle Greek enzymos leavened, from Greek en- en- (II) + zymē leaven; perhaps akin to Latin jus broth, soup — more at juice
1. : any of a very large class of complex proteinaceous substances (as amylases or pepsin) that are produced by living cells, that are essential to life by acting like catalysts in promoting at the cell temperature usually reversible reactions (as hydrolysis and oxidation) without themselves undergoing marked destruction in the process but frequently requiring the presence of activators (as metal ions) or of coenzymes, and that can act also outside of living organisms and therefore are useful in many industrial processes (as fermentation, tanning of leather, and production of cheese) — see -ase ; apoenzyme , ferment 1, substrate
2. : an active system comprising an enzyme usually together with a coenzyme : holoenzyme