Definition of illegal. : not according to or authorized by law : unlawful, illicit; also : not sanctioned by official rules (as of a game)
antibiotic. n. 1. (Pharmacology) any of various chemical substances, such as penicillin, streptomycin, chloramphenicol, and tetracycline, produced by various microorganisms, esp fungi, or made synthetically and capable of destroying or inhibiting the growth of microorganisms, esp bacteria. adj.
Definition of antibiotic. 1. Concept of antibiotic. The word antibiotic is a Greek cultismo, coined in 1942 by the Doctor in biochemistry of Ukrainian nationality, Selman Waksman, coming from biÅtikos consisting of anti meaning against; bio = life and tea room which can be translated as referred to.