vaccine

A preparation of dead or weakened pathogen, or of derived antigenic determinants, that is used to induce formation of antibodies or immunity against the pathogen. (See Polyvalent vaccine, Subunit vaccine.)

A preparation of dead or attenuated (weakened) pathogens, or of derived antigenic determinants, that can induce the formation of antibodies in a host, and thereby produce host immunity against the pathogen. See: sub-unit vaccine, viral vaccine, DNA vaccine, inoculum.

A substance or group of substances meant to cause the immune system to respond to a tumor or to microorganisms, such as bacteria or viruses. A vaccine can help the body recognize and destroy cancer cells or microorganisms.

(vax-EEN): A substance meant to help the immune system respond to and resist disease.

A preparation that stimulates an immune response that can prevent an infection or create resistance to an infection.