Definition of pepsin noun from the Oxford Advanced Learner's Dictionary

 

pepsin

 noun
noun
BrE BrE//ˈpepsɪn//
 
; NAmE NAmE//ˈpepsɪn//
 
[uncountable](biology)
 
jump to other results
a substance in the stomach that breaks down proteins in the process of digestion Word Origin mid 19th cent.: from Greek pepsis ‘digestion’ + -in.
See the Oxford Advanced American Dictionary entry: pepsin