1. A substance, such as penicillin or streptomycin, produced by or derived from certain fungi, bacteria, and other organisms, that can destroy or inhibit the growth of other microorganisms. antibiotics are widely used in the prevention and treatment of infectious diseases.
2. of or relating to antibiotics.
3. of or relating to antibiosis.
4. destroying life or preventing the inception or continuance of life.

1. any substance that can destroy or inhibit the growth of bacteria and similar microorganisms.
2. of or relating to antibiotics.

1. of or pertaining to an antibiotic.
2. having antimicrobial activity; capable of killing microbes.
3. A chemical substance derived from a mold or bacterium that kills microorganisms and cures infections.
4. any chemical substance having therapeutically useful antibacterial or antifungal activity; -- used commonly but loosely for synthetic as well as natural antimicrobial agents.

1. opposed to a belief in the presence or possibility of life.
2. in biology, injurious or deadly to the living substance: as, an antibiotic secretion.

1. a chemical substance derivable from a mold or bacterium that can kill microorganisms and cure bacterial infections
2. of or relating to antibiotic drugs