Literally meaning: “before enzyme”
Origin: Anc Greek
>προ-/pro-(= towards, in front of, before, forward)
+ένζυμο/enzymo(=enzyme) > εν/en(=in) +-ζύμη/zyme(= leaven, ferment )
A proenzyme (or zymogen) is an inactivate form of an enzyme (enzyme precursor) which requires a biochemical change in order to become active.