Vaccine: A substance containing weakened or inactivated forms of a pathogen that, when introduced into the body, stimulates the immune system to produce antibodies and provide protection against the disease.
Antibody:A protein produced by the immune system that binds to a specific antigen, such as a pathogen, and neutralizes or destroys it.
Immunity: The ability of the body to resist a particular infection or toxin, either through the presence of antibodies or the activation of other immune mechanisms.