What does the word vaccinate mean?

The word "vaccinate" means to introduce a vaccine into the body to produce immunity to a disease. Vaccines are biological preparations that provide active acquired immunity against a disease. They are usually made from weakened or killed forms of the disease-causing organism or from parts of the organism. When a vaccine is introduced into the body, the immune system responds by producing antibodies against the disease. These antibodies help the body fight off the disease if it is ever exposed to it in the future.