protease

n. any one of several enzymes that hydrolyze proteins

A protease is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain.
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Protease /pro·te·ase/ endopeptidase. pro·te·ase n. Any of various enzymes, including the proteinases and peptidases, that catalyze the hydrolytic [more]Protease - Community and Resources

Noun
1. any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis
(synonym) peptidase, proteinase, proteolytic enzyme
(hypernym) enzyme
(hyponym) caspase

n. protease, any one of several enzymes that hydrolyze proteins