Antibiotic <!-- google_ad_client = "ca-pub-2327677141881672"; /* Short title Links */ google_ad_slot = "3055805829"; google_ad_width = 468; google_ad_height = 15; //-->

A class of natural and synthetic compounds that inhibit the growth of or kill some micro-organisms. Antibiotics such as penicillin are often used to control (to some extent kill) contaminating organisms.