The Collaborative International Dictionary
propepsin
Pepsinogen \Pep*sin"o*gen\, n. [Pepsin + -gen.] (Physiol. Chem.) The antecedent of the ferment pepsin. A substance contained in the form of granules in the peptic cells of the gastric glands. It is readily convertible into pepsin. Also called propepsin.
Wiktionary
propepsin
n. (context biochemistry English) pepsinogen