Medical Dictionary
10 ENTRIES FOUND:

penicillin

noun pen·i·cil·lin \ˌpen-ə-ˈsil-ən\

Definition of PENICILLIN

1
:  a mixture of relatively nontoxic antibiotic acids produced especially by molds of the genus Penicillium (as P. notatum or P. chrysogenum) and having a powerful bacteriostatic effect against various chiefly gram-positive bacteria (as staphylococci, gonococci, pneumococci, hemolytic streptococci, or some meningococci)
2
:  any of numerous often hygroscopic and unstable amido acids (as penicillin G, penicillin O, and penicillin V) that have a structure in which a four-membered lactam ring shares a nitrogen and a carbon atom with a thiazolidine ring to which it is fused and that are components of the penicillin mixture or are produced biosynthetically by the use of different strains of molds or different media or are synthesized chemically
3
:  a salt or ester of a penicillin acid or a mixture of such salts or esters
April 01, 2015
diapause Hear it
a period of physiological dormancy
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