Main Entry: am·pi·cil·lin

Pronunciation: \ˌam-pə-ˈsil-ən\

Function: noun

: a penicillin C₁₆H₁₉N₃O₄S that is effective against gram-negative and gram-positive bacteria and is used in anhydrous forms, as the trihydrate, or as the sodium salt to treat various infections of the urinary, respiratory, and intestinal tracts—see penbritin