Main Entry: protease inhibitor
Function: noun
: a substance that inhibits the action of a protease; specif : any of various drugs (as indinavir orsaquinavir) that inhibit the action of HIV protease so that cleavage of viral proteins into mature infectious particles is prevented and that are used especially in combination with otherantiretroviral agents in the treatment of HIV infection

protease inhibitor n.
An anti-HIV drug that blocks the action of the enzyme protease, which is needed for viral replication.