pen ‧ i ‧ cil ‧ lin /ˌpenəˈsɪlən, ˌpenɪˈsɪlən/ BrE AmE noun [uncountable]
[ Date: 1900-2000 ; Language: Modern Latin ; Origin: Penicillium name of a type of mold, from Latin penicillus ; ⇨ ↑ pencil 1 ]
a type of medicine that is used to treat infections caused by ↑ bacteria