Nafcillin

Nafcillin sodium is a narrow spectrum beta-lactam antibiotic of the penicillin class. As a beta-lactamase-resistant penicillin, it is used to treat infections caused by Gram-positive bacteria, particularly species of Staphylococci, that are resistant to other penicillins.
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Nafcillin /naf·cil·lin/ a semisynthetic, acid- and penicillinase-resistant penicillin that is effective against staphylococcal infections; used as [more]Nafcillin - Community and Resources

Noun
1. a penicillinase-resistant form of penicillin (trade name Nafcil) used (usually in the form of its sodium salt) to treat infections caused by penicillin-resistant strains of staphylococci
(synonym) Nafcil
(hypernym) penicillinase-resistant antibiotic